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The Health Science Modules of the
Science & Technology Curriculum
Learning and Teaching Resources
Theme: Healthy Lifestyle
Topic:
Substances (Drug) Abuse
The purpose of this set of teaching resources is to provide teachers with
some teaching ideas and updated information on individual themes. The
content of the topics is built on those in the S1-3 Science Curriculum. It
is not expected that every detail in this set of materials is to be covered
in class teaching, as some of the materials only serve as
references/enrichment for teachers. To enhance the effectiveness of
learning and teaching, teachers may need to modify the resources to
suit the needs, abilities and interests of their students. Teachers also
have to note that the materials included are by no means exhaustive,
and should feel free to employ other resources if appropriate.
Table of Contents
Page
Introduction
1
Learning Objectives
2
Scheme of Work
3-7
Lesson Plans
8-11
Teacher Notes

Period 1
12-27

Period 2
28-40

Period 3
41-58

Period 4
59-69
Student Notes

Period 1
70-85

Period 2
86-96

Period 3
97-111

Period 4
112-119
Suggested Activities

Group discussion

Data analysis and information search
120-121

Discussion and information searching
121-122

Knowing the Drugs
122

Debate
123

Visit
123

Interview
123

Design/ Creative Writing/Independent study
123
120
Review Questions/quizzes/food for thought

Quiz for Students
124-127
Tips for Teachers
128-130
Glossary
131-135
Supplementary Resources

References for Teachers
136-141

References for Students
142-143
Drug (Substances) Abuse
Introduction
A number of substances, mainly chemicals and drugs, affect our nervous
system either through their therapeutic actions or side effects. For example,
aspirin and Panadol are common pain-killing drugs but they are not often
misused, while alcohol and tobacco are widely used ‘social’ chemicals.
Some of the drugs are (mis)used as they produce ‘high’ feeling and/or alter
our mood.
In this block, the discussion will mainly focus on those chemicals or drugs that
will change our mood by exerting their major actions in the central nervous
system (CNS). Another reason for concentrating on those drugs or chemicals
is because the word ’substance’ is too broad and general, particularly in
Chinese, which students may find it confusing.
The substances to be discussed are called by various names – hard drugs,
soft drugs, club drugs, party drugs, rave drugs, centrally acting drugs,
psychoactive substances, psychotropic substances, etc. The terms ‘hard’ and
‘soft’ have no scientific grounds; ‘club’, ‘party’ and ‘rave’ refer to the places
where they are (mis)used; ‘centrally acting’ where they exert their actions (the
brain), while ‘psychoactive’ and ‘psychotropic’ are relatively ‘modern’ terms
relate to their mood/mind-altering effects.
[“Psychoactive’ and ‘psychotropic’ have been used interchangeably but there
are some differences. According to Stedman’s Medical Dictionary 26 th Edition,
‘psychoactive’ substances are pharmacological agents that possess the ability
to alter mood anxiety, behaviour, cognitive process, or mental tension, while
‘psychotropic substances’ are drugs used in the treatment of mental illnesses
that are capable of affecting the mind and/or emotion. The above definition
implies that ‘psychotropic substances or drugs’ have potential therapeutic
values, while ‘psychoactive substances or compounds’ may not. For example,
benzodiazepines, cocaine, amphetamines, etc. are usually referred as
‘psychotropic substances’, while organic solvents, cigarette-lighter gas,
alcohol, etc are ‘psychoactive substances’. However, these two terms shall be
used interchangeably in this block.]
1
Learning Objectives:
After this series of classes, the students will be able to
1. To introduce “What are drugs?” different types of drugs and their adverse
effects. This is to remind students that they should use drugs with
extreme care.
2. To provide a brief outline of the drug abuse picture in HK
3. To introduce to students that some substances/drugs alter behavior by
exerting their actions on the CNS.
4. To provide a brief description of the structure and function of the brain
and nerve cells. This part is to provide a scientific basis for the mood,
mind and behavioral altering actions of these substances.
5.
To give some examples of drugs so as to illustrate the diverse and
harmful effects of these substances. The point to be stressed is ‘keep
them at bay’.
6.
To provide preventive means to ‘fight’ drug abuse
You may notice that the content focuses on both social and biological
(medical) aspects. This is because ‘drug abuse’ is also a social issue, so it is
hoped that this approach would to provide a more complete picture of
substance abuse.
2
Scheme of work for Drug Abuse
Scheme of work for Drug Abuse (Healthy Lifestyles theme ~ Health Science Module) (40 mins)
Topic
Time
Learning Objectives
Suggested Activities
Drug abuse Period1 Introduction to Drug Abuse
 Define ‘what is a drug?
1. Quiz

State reasons for studying drug
abuse.
2. Group discussion
Can drugs be classified as ‘hard’ and 1. Data analysis & information
‘soft’?
searching
 Why some drugs are called
2. Discussion & information
‘club/rave’ drugs?
searching
 State some adverse effects of a drug 3. Debate
 Define ‘addiction’
4. Visit 
 State some commonly abused
( For details, see ‘Suggested
psychotropic drugs in HK
activities’ attached)
 State the sources of drugs in HK
5. Design/Creative writing
 Briefly describe the functions of
a) Design a brochure/poster to
different
areas
of
the
brain
warn or educate young people
Scheme of work for Drug Abuse
of the adverse effects of drug
abuse
 Neurons are the basic building blocks b) Imagine you were a drug, what
of the brain
would you do to make an

3
Resources
Readings
1. Wright, D. Human
Physiology and Health,
Heinemann. 2000
2. Becket, B.S. Illustrated
Human Biology, OUP,
1990
Websites
Relevant sites are given
under each topic

Neurons communicate with each
other by using chemicals known as c)
‘neurotransmitters’ or ‘chemical
messengers’ and that centrally acting
drugs exert their actions by
interacting/interfering with the actions
of these chemicals
abuser under you control
Imagine you were the foetus
and you could talk to your
mother. How would you
persuade your mother who was
bearing you to stop
smoking/drinking/taking
ecstasy?
Teachers/students are encouraged to seek relevant activities to strengthen the contents of this block. More relevant
websites are given at the end.
4
Scheme of work for Drug Abuse
Scheme of work for Drug Abuse (Healthy Lifestyles theme ~ Health Science Module) (40 mins)
Topic
Time
Learning Objectives
Suggested Activities
Drug abuse Period 2 Effects of opiates and depressants
(See as above)
 Name some common opiates
 State some effects of opiates
 State the action of opiates
 Name some common depressants
 State the effects of alcohol,
inhalants and ketamine
 State the actions of these
depressants
Resources/References
Teachers/students are encouraged to seek relevant activities to strengthen the contents of this block. More relevant
websites are given at the end.
5
Scheme of work for Drug Abuse
Scheme of work for Drug Abuse (Healthy Lifestyles theme ~ Health Science Module) (40 mins)
Topic
Time
Learning Objectives
Suggested Activities
Drug abuse Period 3 Effects of depressants and stimulants,
(See as above)
and the danger of poly-drug use
 Name some common
benzodiazepines
 State the effects of benzodiazepines
 State the general action of
benzodiazepines
 Name some common stimulants
 State the effects of some stimulants
 State the general action of some
general stimulants
 State what is poly drugs use
 Explain the danger of poly drug use
Resources/References
Teachers/students are encouraged to seek relevant activities to strengthen the contents of this block. More relevant
websites are given at the end.
6
Scheme of work for Drug Abuse
Scheme of work for Drug Abuse (Healthy Lifestyles theme ~ Health Science Module) (40 mins)
Topic
Time
Learning Objectives
Suggested Activities
Drug abuse Period 4 Effects of hallucinogens, harmful effects
(See as above)
of drug abuse and its prevention
 Name some common hallucinogens
 State the action of hallucinogens
 Describe the effects of some
common hallucinogens
 Summarize the harmful effects of
psychoactive substances
 State some signs of drug abuse
 State some means to refuse drug
offer/use
Resources/References
Teachers/students are encouraged to seek relevant activities to strengthen the contents of this block. More relevant
websites are given at the end.
7
Lesson Plan of Drug Abuse
Lesson Plans for Drug Abuse (Healthy Lifestyles theme - Health Science Module)
Suggestions for teaching and activity sequence with time allocation¶
(¶Users may replace some lecturing by introducing some activities described below in class or after school.)
Lesson 1: Social and Scientific Aspects of Drug Abuse (40 min)
Sequence
Content and Activity
Motivation
Show students some newspaper cuttings on drug abuse/Ask some
general questions related to drug abuse
Theme Teaching (a) What is a drug?
(b) What is substance/drug abuse?
(c) Why should you study drug abuse?
(d) Adverse effects of drugs
(e) Sequences leading to addiction
(f) What are rave drugs?
(g) The current drug abuse picture in HK
Consolidation
Q & A or Activity
8
Resources
Newspapers/magazines
(PowerPoint)
PowerPoint lecture
Time
5
30
5’
Lesson Plan of Drug Abuse
Lesson Plans for Drug Abuse (Healthy Lifestyles theme - Health Science Module)
Suggestions for teaching and activity sequence with time allocation¶
Lesson 2: Classification of Psychoactive Substances and General Understanding of the Nervous System
Sequence
Content and Activity
Resources
Motivation
Show students some current newspaper cuttings that are related to PowerPoint Slides
drug abuse and/or ask the following questions:
(a)
Which of the drugs shown on the slide would affect
behavior?
(b)
What would happen after a cup of “black coffee”?
Theme Teaching (a) Classification of psychoactive drugs
PowerPoint lecture
(b) General description of human brain structure and functions 1
(c) Brief description of the structure and functions of a neuron 2
(d) Heroin and its effects
Consolidation
Q & A or Activity
1It
2It
may not be necessary to ask the students to memorize the name of each lobe and the exact functions of each.
may not be necessary to ask the students to memorize the parts of a neuron and the exact functions of each.
9
(40 min)
Time
5
30
5’
Lesson Plan of Drug Abuse
Lesson Plans for Drug Abuse (Healthy Lifestyles theme - Health Science Module)
Suggestions for teaching and activity sequence with time allocation¶
Lesson 3: Effects of Depressants and Stimulants (40 min)
Sequence
Content and Activity 3
Resources
Motivation
Show some newspaper cuttings that are related to drug abuse, or ask PowerPoint Slides
some questions:
(a) What would happen if one takes a sleeping pill?
(b) What would happen if one takes a cup of coffee before going to
bed?
(c) Which is more dangerous: taking sleeping pills with plain water or
sleeping pills with alcohol? Why?
(d) (Illustrate the differences between a depressant and a stimulant.
Remind the danger of poly-drug use.)
Theme Teaching (a) What are depressants?
PowerPoint lecture
(b) Different depressants and their effects
(c) What are stimulants?
(d) Different stimulants and their effects
(Discussion on all depressants and stimulants is not recommended.
Users are advised to choose some common examples to illustrate the
effects/dangers of each class.)
(e) The danger of poly-drug use.
Consolidation
Q & A or Activity
3 It
may not be necessary to ask the students to memorize all effects.
Lesson Plans for Drug Abuse (Healthy Lifestyles theme - Health Science Module)
Suggestions for teaching and activity sequence with time allocation¶
Lesson 4:
Effects of Hallucinogens and Summary of Drug Abuse
10
(40 min)
Time
5
30
5’
Lesson Plan of Drug Abuse
Sequence
Motivation
Theme Teaching
Consolidation
4 It
Content and Activity 4
Resources
Show students some current newspaper cuttings that are related to PowerPoint Slides
drug abuse and/or ask the following questions:
(a) Which of the following is a synthetic hallucinogen: LSD or
marijuana?
(b) What is “marijuana” derived from?
(c) Do drug abusers have some easily recognizable signs?
(a) What are hallucinogens?
PowerPoint lecture
4
(b) Effects of marijuana and LSD
(c) Signs of drug abuse.
(d) Harmful effects of drug abuse.
(e) Penalties for drug- related crimes in HK and neighboring
territories.
(f) Ways to say ‘No’ to drugs.
Q & A or Activity
may not be necessary to ask the students to memorize al effects.
11
Time
5
30
5’
Teacher Notes for Drug
Abuse
PERIOD ONE
(Please refer to the PowerPoint file attached.)
Motivation Questions
(Slide 1)
These are motivation questions attempting to illustrate the scope of this
block. It should be noted that ‘substance abuse’ affects financial and social
aspects in addition to its scientific merits.
What is “Substance Abuse”?
(Slide 2)
Substance abuse’ [ 物 質 濫 用 ] is a very general term. It is too broad,
particularly in Chinese. Students may have difficulties in grasping the
meaning and message. In this block, the discussion shall focus on certain
drugs/chemicals that affect behavior. These are the chemicals that are most
commonly abused in Hong Kong (HK).
Drug abuse is not confined to behavior-modifying drugs only. Other drugs
can be abused. For example, some people may take an aspirin or Panadol
to relief ‘general’ discomfort unrelated to pain and temperature, even though
they know very well that they are painkillers and antipyretics (fever-reducing
drugs).
Besides those mind-altering drugs/chemicals, there are at least two other
types of drugs that are often misused – steroids (particularly testosterones)
and ‘weight-reducing’ drugs. The former is mainly used by body-builders and
weight lifters to enhance their performance through the increase of muscle
mass and strength. Such abuse may lead to unpredictable incidences of
uncontrolled aggressive behavior, or even heart attacks. Other alarming
and dangerous side effects may include feminization in men (such as
atrophy, or decreasing in size, of the testes), masculinization and temporary
infertility in women, liver damage and clogged arteries. Common features
of the female athlete using steroids are leathery skin, bulging muscles and
dense facial hair.
Recently, the use of weight-reducing drugs by ‘over-weight’ or ‘obese’
people to lose weight without exercise is a fashion in HK. Some of these
12
Teacher Notes for Drug
Abuse
drugs achieve weight-reduction by facilitating water-excretion and/or
reducing appetite. Some even contain ‘illegal’ and/or harmful substances.
[Please advise your students to consult their doctors before taking any
weight-reducing drugs. Remind your students the more effective ways of
losing weight are to eat less high-calorie foods and do more exercise, as
described in other lectures of this module. Also, these substances are very
harmful when misused, and should be avoided. These two types of
drugs/chemicals shall not be discussed in this block because of time limit.]
[Please advise your students that drugs prescribed by their doctors are
normally used for short-term only and this use does not usually cause
abuse/addiction and long-term harmful effects. Students should realize that
they don’t have to be afraid of taking drugs when really needed.]
Drug/chemical abuse is a worldwide problem. Among the drugs/chemicals
being abused, psychotropic substances/drugs are most commonly. The
table in the next slide shows the amount confiscated.
Psychotropic drug seizure in different region
(Slide 3)
Recently, psychotropic substance abuse has become a pandemic issue.
In the past, psychotropic substance abuse was mainly confined to opiates
(opium, morphine and heroin). From 1990’s onward, the substances in the
list include amphetamines (there are many types of amphetamine), cocaine,
marijuana, ketamine, sleeping pills (e.g., benzodiazepines), etc. The upward
trend is most striking in Asia (Slide 3).
The aim is to alert students that psychotropic substance abuse is also a
problem in Hong Kong. This part shall be dealt with in more detail in the last
part of this module.
Some reasons for studying drug abuse
(Slide 4)
This slide provides students with some important reasons why ‘Drug abuse’
is an important subject. It is a social issue that requires some scientific
background to understand the problem more fully.
13
Teacher Notes for Drug
Abuse
Drug abuse is an important social problem:Causes heavy financial loss in
society. A large sum of money has to be spent to provide
treatments for addicts. Not to mention the loss in work
production.
2. Rapid increase in drug abusers recently. Drug abusers usually
have poor family and peer relationships. This creates many
social problems.
3. Related to organized crime or triad society activities. Some
triad societies obtained their money supply by operating illegal
drug trades.
Scientific issues:
1. How do drugs affect behaviour? Behaviour is controlled by the
brain. In this block we shall briefly introduce some parts of the
brain that participate more actively in the regulation of
behaviour.
2. What are the effects of drug abuse? We have been told that
these drugs are harmful, but why? And how do they produce
these effects? In this block, we shall introduce the mechanisms
involved.
3. Why do some people use drugs? There are many reasons, and
some of the more important/common ones shall be discussed
in this block.
4. Do abusers display any abnormal signs of habits? The answer
is “yes”. Some abusers have the false belief that no one will
know they take drugs as they do so in “secret places”. This is
wrong. Drug abusers have some easily recognizable signs.[Try
to think of other important reasons to supplement this part.]
Number of people arrested for drug offences
(Slide 5)
This slide below gives a recent picture of drug-related offences in HK.
Major offences: trafficking, possession of large quantity,
reducing/synthesizing etc.
Teacher Notes for Drug
Minor offences: possession of small quantity, taking
drugs, etc.
Abuse
Number of Persons Arrested for Drug Offences
14
12000
10000
8000
major offences
minor offences
Persons Arrested
The point to be stressed is that drug abuse is still a problem in HK despite of
much government efforts.
(Slide 6)
The number of psychotropic drug abusers increased rapidly in recent years.
Two Major reasons: more young people attend rave parties and these drugs
are “readily available” in nightclubs and bars. [Some of these illicit drugs,
e.g., ice, ketamine and sleeping pills, are from Mainland China.]
Reasons for Drug use
(Slide 7)
The slide below provides some reasons for taking drugs.
[Can you think of some other important reasons?]
What is drug?
(Slide 8)
Definition.
A drug is a chemical, other than food, used in the diagnosis,
prevention or treatment of diseases. This is a comprehensive description of
a drug. (For most people, drugs are medicines that can cure or arrest,
relieve symptoms, ease pain, and provide other medical benefits. Defined in
this way, the term ‘drugs’ include essential vitamins and minerals that may
be given to correct deficiency diseases. But it does not include caffeine,
nicotine, alcohol, etc.) The other parts of the definition are to broaden
students’ understanding of a drug.
15
Teacher Notes for Drug
Abuse
[Ask your students whether they can tell the differences between a food and
a drug.]
Concept map on types of drugs
Drugs
Medicinal
Abused
[Please see “Treatment
& Disease” for detail.]
Socially accepted
e.g. caffeine, alcohol, nicotine
(cigarette smoking)
Stimulants
e.g. cocaine, amphetamines,
caffeine, nicotine
Opiates
e.g. opium, morphine, heroin,
methadone
Hallucinogens
e.g. marijuana, LSD
Depressants
e.g. alcohol, barbiturates, sleeping pills,
ketamine
Drugs can be very simple and common compounds. For example, glucose
and sodium chloride can be used as drugs.
1. Diagnosis
a) Glucose is used to diagnose diabetes. How? Patients are asked to
drink a cup of glucose solution then the amount of glucose in the
blood or urine will be determined after a certain period of time. If a
large amount of glucose is found in the blood or urine, the patient is
likely to be suffering from diabetes.
b) Sodium chloride solution, with or without other salts, is administered
to patients who lost a lot of water (dehydration) e.g., in cases of
diarrhea (di-ar-rhea) as a salt replacement.
2. Prevention
An example that drugs used in the prevention of diseases is vaccination,
(e.g., BCG for tuberculosis). This part shall be discussed in the ”Treatment
& Disease” block.
[Ask your students whether they know of the vaccination programme in HK.]
16
Teacher Notes for Drug
Abuse
3. Treatment
Aspirin and Panadol are common painkillers and antipyretics. Antibiotics
are effective drugs used to treat bacterial infections. [Remind your
students that antibiotics are not effective in treating viral infections.] This
part shall be discussed in the ”Treatment & Disease” block.
Side effects of drugs
(Slide 9)
In addition to their therapeutic effects, most drugs have one or more
undesirable effects, and they are:
1. Adverse effects of drugs
They are effects other than the aimed therapeutic effects:
Examples:
a) Aspirin is acidic and too much may cause stomach discomfort and
bleeding (ulcer).
b) Too much Panadol (more than 2 g per day) may result in liver
damage.
c) Taking antibiotics indiscriminately may cause bacteria to become
resistant to antibiotics.
(For more detailed information, you can cross references to
“Treatment & Diseases”, pg 21-25)
2. Overdosage toxicity
Examples:
Taking too much Panadol may cause damages to the liver. Another
example is too many sleeping pills may cause death because extremely
high doses may suppress brain functions and respiration.
3. Allergic reactions
Most drugs are “foreigners” and our body’s immune system may produce
antibodies to attack them, and one the most common reactions is the
appearance of rash over our body.
17
Teacher Notes for Drug
Abuse
Examples:
Some people are allergic to penicillin. Why do some people develop an
allergic reaction after taking a drug while others don’t? It is likely that some
people are just more sensitive than others.
4. Tolerance
This is a situation developed where patients take a larger dose of a drug in
order to achieve the therapeutic effect. Why? It is likely people become
adapted to the dosage or effect of the drug. For example, after prolonged
(chronic) use of aspirin, some people may have to take a larger dosage in
order to have a painkilling (analgesic) effect.
5. Addiction
It is the misuse or harmful use of a drug especially for non-therapeutic
purposes. Certain drugs are generally misused because they alter mood or
behavior. Thus, an understanding of their properties is important to an
understanding of their abuse.
However, drug abuse does not depend entirely on the pharmacological
properties of a drug as NOT everyone uses the same drug to the same
extent. There are two major reasons for drug abuse:
“addiction”.
“habituation” and
a.
Habituation is mainly due to psychological dependence. Alcohol,
one the most commonly misused drugs, is abused because it is
freely available in our society. To some, it relieves anxiety and
facilitates participation in social situations. Because of these and
other reasons, some people believe that alcohol abuse is mainly a
“bad” habit. However, prolonged use may lead to addiction and
the situation is – “alcoholism”.
b.
Addiction develops because of tolerance and psychologic as well
as physical dependence.
Definition of Addiction: “Addiction” is a disease process characterized
by the continued use of a specific drug (or psychotropic substance)
despite physical, psychological or social harm.
18





Teacher Notes for Drug
Abuse
Addiction is a disease according to some psychiatrists. Drug use or
abuse crosses the line to drug addiction when one needs to have
the drug, and increases the amount of the drug.
Various factors, such as personality, genetic makeup and peer
pressure affect the likelihood of becoming addicted to a drug. In
addition, some drugs such as heroin and cocaine more quickly
produce a physical addiction than some other drugs for many
people.
Some scientists believe that addiction is a disorder or disease of
the brain. The parts of the brain responsible for reward, pleasure
and reinforcement simply don't work well enough in the addicted
person. This condition is thought to be either genetically acquired or
due to environmental stressors combined with prolonged or
excessive ingestion of the addictive substance.
The slang for addiction is “hooked”. Being hooked means the addict
has difficulty in giving up the drug even given maximal assistance.
Addiction is not limited to drugs. For example, "Internet Addiction" is
a term coined to describe pathological Internet use.
References:
1.
http://mentalhealth.about.com/library/sci/0201/blgenedrug201.htmhttp://
3.
homeworktips.about.com/library/blantidrug.htm
http://www.addictionscience.net/ASNprimer.htm
Sequence leading to addiction
(Slide 10)
1. Experimental use.
Most drug abuse begins with experimental or exploratory use. After
which the person may either reject the use of the drug or progress to
one of the patterns of use given below.
2.
Social use.
Some drugs tend to be used with a group of “friends”. Social users do
so because individuals form attitudes and react as members of the
group. The attitudes and problems of their group will condition their use
of drugs and their reaction toward people who choose to use drugs.
One common example is alcohol. The danger of social use of drugs is
19
Teacher Notes for Drug
Abuse
that it increases the chance of those individuals who are vulnerable to a
more serious and destructive pattern of misuse.
3.
Episodic abuse.
This is a pattern where an excess amount of drugs is used, either when
the individual is with his/her friends or even alone. The major difference
between experimental use and social use is that the amount of drug
used is much larger.
4.
Tolerance.
A person needs to increase the dosage of a medication over time in
order to receive the same therapeutic benefits. [Studies show that the
majority of people with anxiety disorders do not increase their
benzodiazepines (a kind of anti-anxiety/sleeping pill) dosages over time;
in fact, most lower their dosages. However, in drug abuse, tolerance
often develops. The point to be stressed that ‘proper medical’ use does
not cause addiction.]
5.
Addiction.
The major difference between this type of abuser and those of above is
that addicts (compulsive abusers) have difficulty giving up their habits
when given maximal assistance. Example: some smokers cannot
perform their jobs properly with a cigarette in hand. Also, alcoholics
don’t eat at all without alcohol.
Misconception of ‘hard’ and ‘soft’ drugs
(Slide 11)
1. These terms – ‘hard’ and ‘soft’ do not reflect their textures or forms.
2.
3.
Drugs that are subject abuse were divided into ‘hard’ and ‘soft’. It was
believed that soft drugs were not or less harmful and addictive drugs.
These sayings are now considered to be wrong and unfound.
Those ‘soft’ drugs are so called possibly because some of them are
prescription drugs e.g., Valium (a sleeping pill), so, the false belief arose
that they were less harmful. [Note that long-term use of a drug in large
quantity can lead to addiction.] Also, the penalties for possessing ‘soft’
drugs are less harsh than those of ‘hard’ drugs, e.g., morphine or
heroin.
20
4.
Besides being classified as ‘hard’ and ‘soft’,
drugs are
often
Teacher
Notes
forcategorized
Drug
into ‘socially acceptable’ and ‘socially unacceptable’,
‘legal’ and ‘illegal’,
Abuse
‘pharmaceutical’ and ‘recreational’. Depending on their use, some drugs
may fall into a number of categories.
[Remind your students that similar to heroin abuse, psychotropic substances
abuse, also cause serious harmful effects on our mental and physical health,
family and peer relationships, school (pursuits or works, social life and work
performance, etc.)
What are club/party drugs?
(Slide 12)
Besides the unscientific classification of drugs into ‘hard’ and ‘soft’, some
drugs are called club/rave drugs. They are relatively trendy terms. They are
drugs mainly used in parties, bars and entertainment places.
What are they?
Most of them are mind-altering drugs. [Remind your students that NOT all
rave partygoers use drugs. They should have a good knowledge of the
party/place before they attend.]
Why are they abused?
These people believe that they can produce ‘high’ feelings. [Remind your
students ‘high’ experience in a party depends on the atmosphere of the
place, music and surrounding friends but NOT on drugs.]
Why are these drugs abused?
Because most of the people attending these events/functions are teens and
young adults, and they are the group of people who are likely to seek
something ‘new’ and excitement - ‘high feeling’. Also, these drugs are
usually in pill or powder forms so they can be easily carried to these places
and that they dissolve in drinks readily.
Examples:
GHB, Valium (a kind of sleeping pill), and ketamine are predominantly
central nervous system depressants. In low doses, they can suppress
shyness. Ice, ecstasy and cocaine are stimulants, and people become more
talkative after taking these drugs.
21
22
Teacher Notes for Drug
Abuse
Some characteristics of those drugs:




Colorless
Tasteless
Odorless
Can add to beverages and ingested unknowingly
Some of them are called “date rape drugs” because they have the above
characteristics.
How are psychoactive substances taken?
(Slide 13)
This slide is to inform students how are these drugs taken. The purpose is
that students by knowing the routes/ways they can tell whether his/her
friends are drug abusers.
1.
Like most drugs, psychoactive substances are taken orally.
Examples: amphetamines, sleeping pills, cough syrups, etc.
2.
Morphine, heroin and other clinically used psychotropic substances are
usually taken by injection. This route of administration gives a very
quick response to the drug(s) administered. However, this route is also
the most dangerous one as it readily causes overdose toxicity or even
death.
Why? This is because most of the street-drugs (a) contain impurities;
and (b) package dosages vary with sources, illegal supply and price.
Moreover, it is also the major cause of AIDS and hepatitis (inflammation
of the liver) as well as other dangerous infectious diseases.
3.
Inhaling or sniffing is used for taking marijuana, cocaine, nicotine
(smoking), paint thinner, model glue etc. This is also elicits fast
responses, as soon as substances are inhaled, they enter the blood
stream through the lungs then travel to the brain. This route of taking
drugs may cause damage to the nose, respiratory tract and lungs.
4.
Substances that are fat-soluble, e.g. paint thinner can be absorbed
through skin contact. The amount absorbed through this route is very
small and the response generated is very mild. This route is rarely
used.
23
Teacher Notes for Drug
Abuse
Another point that can be mentioned is that most of the psychoactive
substances are fat-solute compounds. This property allows
psychoactive substances to enter the brain more readily because the
brain and the blood stream are separated by a “blood-brain barrier”, a
hurdle that prevents/reduces non-fat soluble compounds, but allows
fat-soluble substances to enter the brain by diffusion as fat-soluble
substances can diffuse through cell membranes that are composed of a
lipid bilayer membrane.
Regardless of the routes of administration/taken, these substances
finally enter the brain to exert their mind-altering affects. This is the
reason why an understanding of structure and function of the brain is
essential.
(Slide 14)
These are lead questions related to classification of drugs and brain
structure and function.
Central Nervous System
(Slide 15)
This slide describes the structure and function of the central nervous system.
The point to be stressed is that the brain or the central nervous system is the
most important organ in our body that controls our behavior.
Function of the brain
(Slide 16)
The major reason for introducing functions of the brain is to give students the
idea that different areas control different functions. The purpose is to
provide students with a scientific background so that they would understand
effects of various drugs better.
Some of the major functions of the nervous system are:
1. Organize and direct behaviour – speech, reflex, etc
2. Monitor the outside world – with our eye, ears, nose, etc.
3. Learning and memory – improve our quality of life, survival, etc
4. Thinking – generates ideas, develops personality, etc.
24
Teacher Notes for Drug
Abuse
To arouse students’ interest in brain structure and function, the following
points may be helpful:
1.
The cerebrum is divided into two hemispheres: left and right. The left
controls the motor and sensory activities of the right side of our body
and vice verse. [How do we know? Patients who suffer from severe
stroke on the left hemisphere lose some of the functions of right hand
side of their bodies.]
2.
The area that controls speech for most right-handed people is ‘mainly’
located on the left hemisphere. For left-handed people, both brain
3.
hemispheres control speech. How do we know? Also, data from stroke
patients.
Some other functions, such as judgment, reasoning, memory, etc, are
controlled by both hemispheres. These may explain why these functions
are not totally lost in stroke patients.
The concept that different brain areas perform different function is important
for students to understand why certain psychoactive substances have
multiple effects on behavior. The answer is that these substances can affect
one or more neurotransmitter system(s) in different areas of the brain.
[Note that knowing the details of different parts of the brain and their
functions are not intended. In delivering this part, please stress “different
areas of the brain perform different functions”. This means that certain
functions are mainly localized in certain area(s) of the brain.]
Functions of neurons
(Slide 17)
This part introduces the basic concept of (chemical) neurotransmission, i.e.,
how are signals from one neuron passed to another by using chemicals
known as neurotransmitters. The reason for including this is to inform
students that psychoactive substances affect neurotransmission to achieve
behavioral changes.
[Details of neurotransmission processes are not recommended.]
25
Teacher Notes for Drug
Abuse
Neuron is one of the major cell types in the nervous system. The other is
glial cell. Glial cells may be considered as supporting cells in the nervous
system as they do not participate directly in neurotransmission.
Unlike liver cells and red blood cells, neurons have many shapes.
[Please consult a senior form biology textbook for diagrams and details.]
Their function is to transmit signals. They do so by using different
neurotransmitters. At present, there are at least 50 neurotransmitters known.
[If ‘neurotransmitter’ is too big a word for your students, consider calling
them ‘mail carriers’. This is analogous to different letter-carriers carry
different kinds of mails to different areas, or persons. ]
Structures of a neuron
(Slide 18)
This slide provides a schematic drawing of a neuron. It may not be
necessary to ask students to memorize all the terms.
The major points to be noted are:
1. At one end (left-hand side), the cell body where the nucleus is, the
nerve cell (neuron) serves as an antenna. It receives signals from
2.
3.
adjacent neurons. At the terminal (right-hand side), the signal is relayed
to the other adjacent nerve cell. The axon is just a cable where signals
pass from one end (cell body) to the other (the nerve terminal).
The two adjacent neurons are NOT in direct contact with one another.
This leads to the question of how signals pass from one neuron to
another or neurotransmission.
The process involved is known as ‘chemical neurotransmission’. Briefly,
signals pass from one neuron to another by causing neurotransmitter
release at the nerve terminal, the neurotransmitter released at the
4.
synaptic cleft binds to specific receptors situated on the plasma
membrane of the postsynaptic cell. Repeating the above processes
would enable signals to pass to another neuron.
At present, there are more than 50 neurotransmitters known. For
simplicity, you may equate ‘neurotransmission’ to the ‘mail delivery
system’, and ‘neurotransmitters’ to ‘letters’ delivered to different
addresses written on the envelope. As the contents in the letters are
different, the messages delivered are also different.
26
5.
Teacher Notes for Drug
Abuse
If this mail delivery system goes astray, the situation will become
chaotic. Mind-altering drugs affect brain functions by interfering the mail
delivery system – neurotransmission, in the brain.
Psychotropic drugs
(Slide 19)
Definition: Psychotropic drugs are substances that possess the ability to
alter mood, anxiety, behavior, cognitive processes or mental tension.
Commonly abused mind-altering drugs may be arbitrarily and broadly
divided into three groups:
1.
2.
3.
Therapeutic drugs, i.e., drugs with clinical applications (e.g.
benzodiazepines, ketamine, morphine, etc)
Socially accepted drugs/chemicals (e.g. alcohol and tobacco)
Drugs of abuse, i.e. drugs with little or no clinical applications (e.g.
heroin, amphetamines, cocaine, LSD and marijuana).
In this block, these drugs are classified in a more scientific way into five
categories, according to their clinical applications, actions and effects.
1.
2.
3.
4.
5.
Narcotic analgesics
Depressants
Stimulants
Hallucinogens
Antipsychotics
Some examples and how they affect the central nervous system are
described in this block.
The classification adopted is a simplified one. Three points need clarification:
1.
Depressants in here include both tranquilizers and depressants
because both groups of drugs slow/suppress neuronal activities. In
most pharmacological textbooks, benzodiazepines are classified under
‘tranquilizers’, while barbiturates, methaqualone and gamma
hydroxybutyric acid (GHB, or its salt, gamma hydroxybutyrate) are
depressants. Clinically, some depressants have sedative, hypnotic and
anti-epileptic effects, and benzodiazepines have hypnotic and
27
Teacher Notes for Drug
Abuse
anti-anxiety effects. However, all these substances are groups under
‘depressants’ in this block. This grouping is to relieve students’ burden
and to avoid lengthy pharmacological explanations.
2.
Ketamine is used clinically as a surgical anaesthetic, meaning that it
suppresses neuronal activity in the brain. So, it classified as a
depressant in this block. Because it also induces hallucinations, some
people in the drug abuse circles classify it as a hallucinogen.
3.
Anti-psychotics, drugs used to treat schizophrenia, depression, etc, do
not induce euphoria and other ‘pleasant’ feelings. They are rarely
abused and therefore not discussed in this block. (For more detailed
information, you can cross references to ’Mental Health’, pg 16-22).
Commonly abused drugs of all people in Hong Kong
(Slide 20)
The most commonly abused drug in Hong Kong is still heroin. It had been so
for many years. This may be related to the history that opium was the first
mood-altering drug used in HK in the Ching Dynasty. At present, most of the
heroin abusers are older than 21, and the number of heroin abusers are
decreasing compared to a few years ago. One of the reasons may be due to
the effectiveness of the Government’s anti-drug campaign and rehabilitation
programmes.
On the other hand, psychotropic drug abuse is becoming more popular.
Psychotropic substance abuse has been on the rising trend in North America
and Europe in recent years, and perhaps HK people are just following.
Amongst the drugs, ketamine, ice, sleeping pills and ecstasy are some
‘popular’ drugs.
Commonly abused drugs by person under 21 in Hong Kong
(Slide 21)
Abuse of psychotropic drugs in HK is getting more popular in persons under
21. The reason is not very clear. One possible reason may be due to
American and European influence. Another possible reason might be due to
the misconception that they are ‘soft’ drugs and this creates the false belief
that they are less harmful.
28
In HK, the most ‘popular’ drugs are ecstasy and ketamine. These and other
psychotropic drugs are easily available in the black market or certain
entertainment places.
Sources of drugs in Hong Kong
(Slide 22)
This slide informs students where do these drugs come from. As drugs are
neither planted nor manufactured in HK, all illicit drugs (chemicals) seized
locally are smuggled into HK.
Smuggling by land is the means by which most heroin and ice reach HK.
Heroin, which is produced in the Golden Triangles, is infiltrated into the
Mainland via its land borders, stored in Guangdong Province then shipped to
HK. Ice is similarly conveyed to HK across the land border.
Bulky drugs, e.g., cannabis, are smuggled by maritime routes.
[In delivering this part, please stress that all illegal drugs may contain deathly
impurities. Gather some newspaper cuttings to illustrate points discussed
in this slide. As an activity in class, you may ask your students to think of
ways to prevent illicit trafficking of these drugs.]
End of Period 1
29
Teacher Notes for Drug
Abuse
PERIOD TWO
Lead questions related to this period.
(Slide 24)
Narcotics analgesics (Opiates)
(Slides 25-29)
Definition: Opiates are compound that have clinical properties similar to
morphine, i.e., they have analgesic effects.
There are four major forms of opiates:
1. Heroin
2. Morphine
3. Opium
4. Codeine (found in cough syrups)



Heroin is processed from morphine, a naturally occurring substance
extracted from the seedpod of the poppy plant Papaver somniferum
(this Latin name means “the poppy that makes you sleep”.
Among them, heroin (diacetylmorphine) is the most potent and highly
addictive opiate, and is the major abused substance in HK. The
presence of the two acetyl groups make heroin more fat-soluble and
thus enters the brain more readily.
In the manufacturing of heroin, acetic anhydride is required to convert
morphine to heroin (diacetylmorphine). This explains why possession of
acetic anhydride is unlawful.
[Puzzle: Do poppy seeds ( 罌 粟 籽 ) used in some recipes contain
morphine? The answer is no. Morphine is found in the sap obtained by
scraping the young fruit. When the fruit is allowed to ripen after
scraping, and the seeds do not have morphine.]
Street/Other namesHeroin is typically sold in the black market as a white or
brownish powder. Street names for heroin include ‘smack’, ‘H’, ‘skag,’ and
‘junk’. Other names may refer to types of heroin produced in a specific
geographical area, such as "Mexican black tar."
Most street heroin is “cut” (diluted) with other drugs or with substances such
as sugar, starch, powdered milk, acetaminophen ( 必 理 痛 ) or quinine.
Street heroin can also be diluted with strychnine or other poisons. Because
30
Teacher Notes for Drug
Abuse
heroin abusers do not know the actual strength of the drug or its true
contents, they are at risk of overdose or death.
Clinical uses of Opiates
Opiates and their synthetic counterparts (commonly called synthetic opiates)
are used in modern medicine to relieve acute pain suffered as a result of
disease, surgery, or injury; in the treatment of some forms of acute heart
failure; and in the control of moderate to severe coughs (codeine) or
diarrhea. Among them, morphine is commonly used for relief of severe pain
in the care of the terminally ill.
How is it abused?
1. Heroin is usually injected, sniffed/snorted or smoked.
2. Intravenous injection provides the greatest intensity and most rapid
euphoria. This is because it enters the brain most rapidly and
completely.
3. Intramuscular injection produces a slower onset of euphoria and that of
sniffing and smoking is slower.
4. Like other street psychoactive substances, purities and concentrations
of heroin from different black market sources create dangerous
problems that can be fatal.
5.
6.
Opium appears either as dark brown chunks or in powder form, and is
generally eaten or smoked.
Researchers have confirmed that all forms of opiate when used
regularly and in large doses are addictive.
How does it exert its effects?
1. Heroin is much more fat-soluble than morphine (because it has two
acetyl groups), it can enter the brain very rapidly.
2. Soon after injection (or inhalation), heroin crosses the blood-brain
3.
4.
barrier enters the brain.
In the brain, heroin is converted back to morphine and binds rapidly to
(opioid) morphine receptors. [A receptors is a large protein molecule in
the plasma membrane that a neurotransmitter binds specifically.]
Opioid receptors are pain-suppressing receptors in the brain. Note that
our brain also produces pain-killing substances called ‘enkephalins’. [An
enkephalin is a peptide produced by the brain that has opioid/pill-killing
activity.]
31
Teacher Notes for Drug
Abuse
Short-term effects
1. After an injection of heroin, the user reports feeling a surge of euphoria
("rush") accompanied by a warm flushing of the skin, a dry mouth, and heavy
extremities. Following this initial euphoria, the user goes "on the nod," an
alternately wakeful and drowsy state.
2. Mental functioning becomes clouded due to the depression of the central
nervous system. Morphine and other opiates have depressive effects on
respiration. At high doses of opiates, respiration may become so slow or
irregular as to be life threatening and result in death. Pupil constriction and
constipation are some common symptoms of opiate abuse.
3. Heroin addicts are at very high risk for contracting AIDS, hepatitis and
other infectious diseases. This is because heroin addicts may share or reuse
injection needles and syringes with infected individuals.
4. In addition to the effects of the drug itself, street heroin may have
additives that do not readily dissolve and result in clogging the blood vessels
that lead to the lungs, liver, kidneys, or brain. This can cause infection or
even death of small patches of cells in vital organs.
Long-term effects
1. Long-term effects of heroin appear after repeated use for some period of
time. Chronic users may develop collapsed veins, infection of the heart lining
and valves, abscesses, cellulitis (inflammation of connective tissues), and
liver disease.
2. Pulmonary complications, including various types of pneumonia, may
result from the poor health condition of the abuser, as well as from heroin's
depressing effects on respiration.
3. With regular heroin use, tolerance develops. This means the abuser must
use larger doses of heroin to achieve the same
intensityNotes
or effect.
As higher
Teacher
for Drug
doses are used over time, physical dependence
and addiction develop. With
Abuse
physical dependence, the body has adapted to the presence of the drug and
withdrawal symptoms may occur if use is reduced or stopped.
32
Withdrawal, which in regular abusers may occur as early as a few hours
after the last administration, produces drug craving, restlessness, muscle
and bone pain, insomnia, diarrhea and vomiting, cold flashes with goose
bumps ("cold turkey"), kicking movements ("kicking the habit"), and other
symptoms. Sudden withdrawal by heavily dependent users who are in poor
health is occasionally fatal.
Effects on pregnancy
Heroin abuse can cause serious complications during pregnancy, including
miscarriage and premature delivery. Children born to addicted mother are at
greater risk of suffering from ‘sudden infant death syndrome.
Treatment
There is a broad range of treatment options for heroin addiction, including
medication as well as behavioral therapies.
Methadone, a synthetic opiate medication that blocks the withdrawal effects
of heroin for about 24 hours, has a proven record of success when
prescribed at a high enough dosage level for people addicted to heroin.
There are many effective behavioral treatments available for heroin
addiction. These can include residential and outpatient approaches.
Several new behavioral therapies are showing particular promise for heroin
addiction.
Contingency management therapy uses a voucher-based system, where
patients earn "points" based on negative drug tests, which they can
exchange for items that encourage healthful living.
Behavioral interventions are designed to help modify the patient's thinking,
expectations, and behaviors and to increase skills in coping with various life
stressors.
Other treatment methods that may be used as part of the rehabilitative
process include: hospitalization in highly controlled, drug-free environments
as well as outpatient programs, including methadone maintenance for heroin
addicts.
33
Teacher Notes for Drug
Abuse
In addition to treatment, self-help groups for substance-abusing individuals
as well as their family members are useful in providing support and
reinforcing treatment.
References:
http://www.nida.nih.gov/ResearchReports/Heroin/Heroin.html
http://www.nlm.nih.gov/medlineplus/heroinabuse.html
Lead questions related to depressants.
(Slide 30)
Depressants/ sedative hypnotic compounds
(Slide 31)
These substances can depress central nervous system (CNS), neuronal
activities and are capable of inducing sedation, sleep (hypnosis) and
behavioral alterations, so they are known as ‘depressants’ or ‘sedative
hypnotic’ compounds.
Some of them are prescribed to treat insomnia (sleeping pills), anxiety
(benzodiazepines) and epilepsy (barbiturates) [For simplicity, these drugs
are grouped under “depressants” in this block.]
What are CNS Depressants?
(Slide 32)
This slide provides a brief description of (CNS) different kinds of
depressants.
In this block, psychoactive substances belonging to this class are simply
called (CNS) depressants. This is an easier term for students. Alcohol and
inhalants are general depressants as they slow all nerve activities in our
body, while others exert their actions mainly in the brain, therefore known as
CNS depressants. As explained earlier, drugs in this group include:
tranquilizers and depressants.
Some depressants have therapeutic
applications, while other don’t.
The depressants discuss in this block are: alcohol, inhalants, ketamine,
benzodiazepines, and gamma hydroxybutyrate (GHB).
34
Teacher Notes for Drug
Abuse
A. Ethyl alcohol
(Slide 33)
Ethyl alcohol is a nonselective CNS depressant because it affects all parts of
the CNS. Alcohol and cigarette are the most commonly used chemicals.
Frequently Asked Questions.
(A) Does food slow alcohol absorption?
Yes. Food in the stomach slows alcohol absorption for two reasons:
1.
By diluting the alcohol and covering some of stomach membranes
through which alcohol would be absorbed.
2.
By prolonging the emptying time. Thus, blood levels of alcohol will
increase much faster in an individual who has fasted than in
someone who has just eaten a heavy meal. However, in either
case, the alcohol will be completely absorbed; it is only that the
absorption is delayed in the well-fed individual.
(B) What is ‘wood alcohol’? Why is it toxic?
Methyl alcohol (wood alcohol; sometimes found as an adulterant in
illegal liquors) is toxic. The lethal dose is 2-8 oz (~60-220 ml).
1.
2.
3.
4.
5.
Methyl alcohol enters the brain more rapidly than ethyl alcohol.
Upon metabolism (in the liver), it is converted to formic acid and
formaldehyde.
Formic acid causes acidosis (decrease in body pH and this can be
fatal).
The optic nerve (the nerve that connects the eye to the brain) is
most sensitive to acidosis and this may result in blindness,
[Blindness or impaired vision may be permanent.]
Other effects include: headache, dizziness and nausea.
One treatment for methyl alcohol toxicity is to give ethyl alcohol.
The rationale is that both methyl and ethyl alcohol use the same
set of metabolic enzymes, thus taking ethyl alcohol would reduce
the formation of formic acid and formaldehyde.
35
Teacher Notes for Drug
Abuse
Relationship between blood alcohol concentrations & pharmacological
effects
(Slide 34)
The data provide an idea that the severity of alcohol intoxication increases
with the amount of alcohol ingested.
Blood alcohol concentrations (BACs) and driving
Blood alcohol concentration (BAC) is the amount of alcohol in the
bloodstream. It is measured in percentages. For example, having a BAC of
0.10 percent means that a person has 1 part alcohol per 1,000 parts blood in
the body.
The drink driving legislation was first introduced in Hong Kong in December
1995. The prescribed legal limit of BAC was 0.08% (80 mg of alcohol per
100 ml of blood). In response to the community's concern over drink driving
and having reviewed the effectiveness of the legislation, the HKSAR
tightened the legal limit of BAC in October 1999 from 80 to 50 mg of alcohol
per 100 ml of blood (i.e. 0.05 percent), same as in places like Germany,
Australia and Japan.
Major reasons for lowering the legal limit of BAC are based on studies of
alcohol-related traffic accidents, reaction time, tracking ability, concentrated
attention ability, divided attention performance, information process
capability, visual functions, perceptions, and psychomotor performance.
Impairment in all these areas was significant at blood concentrations of 0.05
percent. These studies found that impairment first appeared in many of
these important areas of performance at BAC of 0.02 percent, substantially
below the legal limit in the HKSAR. Note that deterioration in driving skills
progresses rapidly with rising BAC.
[Activity: ask your students to find out the percentage of traffic accidents that
are related ‘drunken’ driving.]
36
Teacher Notes for Drug
Abuse
Effects on alcohol
(Slide 35)
Depending on the amounts ingested, alcohol can cause various effects.
1. Psychomotor performance (see information listed above).
2. Chronic use and in large amount, alcohol replaces a part or most of
the normal diet. The calories derived from alcohol are
unaccompanied by vitamins and protein and this results in
malnutrition.
3. Chronic use causes degenerative changes in the nervous system
that is characterized by poor memory in recent events.
4. Chronic use and large consumption causes permanent liver
damage. For example, fatty liver because alcohol ingested is
converted to fat which deposits in the liver. The fatty changes are
reversible, but they may lead to hepatitis and liver cirrhosis.
B. Inhalants
(Slides 36 –40)
What are inhalants?
Inhalants are volatile substances that producing chemical vapors that can be
inhaled to induce psychoactive, or mind-altering, effects. [Although other
abused substances can be inhaled, the term "inhalants" is used to describe
a variety of substances whose main common characteristic is that they are
rarely, if ever, taken by any route other than inhalation.]
“Inhalant abuse” refers to the intentional breathing of gas or vapors with the
purpose of reaching a high feeling.
Because there are a large number of chemicals that can produce vapors at
room temperature, a precise categorization of inhalants is difficult. One
classification system lists four general categories of:
1. Volatile solvents (see below for details)
2. Aerosol, e.g., spray paints, deodorant and hair sprays
3. Gases, e.g., medical anesthetics (ether, chloroform, halothane, and
nitrous oxide, commonly called "laughing gas.")
4. Nitrites-based on the form in which they are often found in
household, industrial, and medical products.
37
Teacher Notes for Drug
Abuse
[Abuse of aerosols, gases and nitrites-based inhalants are rather uncommon
in HK, and their abuses will not be further discussed.]
Volatile solvents
 Volatile solvents are liquids that vaporize at room temperatures.
 They are found in a multitude of easily available products used for
common household and industrial purposes.
 These include:
1. Paint thinners and removers,
2. Dry-cleaning fluids,
3. Degreasers,
4.
5.
6.
7.
8.
Gasoline,
Glues,
Correction fluids,
Felt-tip marker fluids, and
Cigarette lighter fuel.
How are inhalants used?
Inhalants are usually taken by sniffing.
Short-term effects
At low doses, inhalants produce disinhibition (high feeling, euphoria etc.) at
early stage. The reason is that low concentrations of inhalants inhibit the
inhibitory neurons in the nervous system.
At high doses, they depress neuronal activity, vital organ functions and in
severe cases, death. In most cases, respiration is slowed.
[The specific effects of different types of inhalants are given in Slide 39.
Most of the effects described in Slide 40 are due to the actions of various
inhalants in the brain.]
Long-term effects
Inhalant abuse has been shown to cause liver, kidney and brain damage
and these harmful effects can also occur in the fetus. They cause these
long-term effects, as inhalants are fat-soluble substances.
38
Teacher Notes for Drug
Abuse
Effects on pregnancy
Similar to other substances of abuse, inhalants also affect the developing
fetus because they dissolve and accumulate in fatty tissues.
Moreover, a "fetal solvent syndrome" can occur has been suggested.
Because of their potential serious effects, pregnant women should avoid
exposure to solvents.
Treatment
The general treatment of withdrawal from solvents is similar to that for
alcohol - calm reassurance in an area of low-level sensory stimuli, and drug
treatment is not usually required.
Detoxification from solvents, however, takes much longer than from alcohol:
short term detoxification requiring from 2 weeks to 30 days. This is because
they are rather fat-soluble and can accumulate in fatty tissues.
For details, see: http://corp.aadac.com/drugs/beyond/Solvents.asp
C. Ketamine
(Slides 41-43)
What is ketamine? Ketamine is a depressant and an anaesthetic, which has
hallucinogenic action.
History
It was first synthesized in 1962 by Calvin Stevens at Parke Davis Labs (a
drug company) while searching for a replacement for PCP (phencyclidine),
an anaesthetic compound that can induce undesirable hallucination.
Ketamine was later used recreationally and called a "dissociative
anaesthetic" (a compound that produces an anesthetic effect characterized
by a feeling of being detached from the physical self or the actual/real
environment).
Ketamine abuse grew through the 1980s and 1990s, and recently ketamine,
together with GHB (gamma hydroxybutyrate) and Rohypnol (a kind of
sleeping pill), are ‘popular 'date rape’ drugs in the US. In Hong Kong, it is
one of the popular 'club drugs'.
39
Teacher Notes for Drug
Abuse
[Note that possession of these drugs is also illegal in HK.]
Street/Other namesSlang terms of ketamine in the North America include,
‘K’, ‘Special K’, ‘Ketaset’, ‘Ketalar’, ‘Vitamin K’, ‘Lady K’, ‘Super K’, ‘OK’,
‘KO’, ‘Kid Rock’, ‘Ket Kat’, ‘Make-Her-Mine’, etc.
In undiluted form it looks like an off-white powder, in diluted form it looks like
slightly cloudy water.
Clinical usesKetamine is an anaesthetic used primarily for veterinary
anesthesiology.
2.
3.
Ketamine was originally used for anesthesia because it suppresses
breathing much less than most other available anesthetics, but in the
1970's patients began to report unwanted/undesirable visions while
under its influence.
Although ketamine is not used medically on humans much because it
induces psychedelic episodes in patients, it is still used for some limited
human applications because it does not depress breathing or
circulation. This is because ketamine blocks nerve paths
(neurotransmission) without depressing respiratory and circulatory
functions, and therefore acts as a safe and reliable anaesthetic.
[This is why ketamine is classified as an anaesthetic and a depressant
in this block.]
How is it used?Although it is manufactured as an injectable liquid, in illicit
use ketamine is generally evaporated to form a powder that is snorted or
compressed into pills.
Ketamine is used recreationally primarily as a snorted white powder and for
therapeutic and psychedelic use it is often injected intra-muscularly.
Ketamine is odorless and tasteless, so it can be added to beverages without
being detected, and it induces amnesia (loss of short-term memory).
Because of these properties, the drug is sometimes given to unsuspecting
victims and used in the commission of sexualTeacher
assaultsNotes
referred
as "date
forto
Drug
–rape drug".
Abuse
How does it exert its effects?
40
When snorted or smoked, ketamine rapidly passes to the brain to disrupt the
functioning of sites known as NMDA (N-methyl-D-aspartate) receptor
complexes, which are receptors for the neurotransmitter glutamate.
Glutamate transmission systems in the brain play a major role in the
perception of pain, in cognition - including learning and memory and in
emotion.
In the brain, ketamine also alters the actions of dopamine, a
neurotransmitter responsible for the euphoria associated with many abused
drugs.
(For details see:
http://www.erowid.org/chemicals/ketamine/ketamine_journal3.shtml.)
The above explain the diverse effects of ketamine.
Short-term effects
Ketamine is a unique drug in that it has hypnotic (sleep producing),
analgesic (pain relieving) and amnesic (short term memory loss) effects.
[In the recreational drug culture, ketamine is referred to as a hallucinogenic
or "dissociative." This refers to the feeling that the mind is separated from
the body. It induces a feeling of euphoria causing mild hallucinations with
effects similar to those produced by PCP combined with visual effects similar
to those of LSD.
[Because of the hallucinogenic effect, ketamine is classified as a
hallucinogen by some drug-abuse agencies.]
The most common effects include:
 Hallucinations




Confusion
Euphoria
Increased sociability
Clumsy, or 'robotic' movement (which lead to delayed reaction time,
irrationality, violent or aggressive behavior).
41
Teacher Notes for Drug
Abuse
Negative physical effects can include:




Dry mouth
Depressed respiration
Racing heart.
Nausea and/or vomiting (a common problem when taking an
anesthetics or sedatives).
With larger doses, it can lead to oxygen starvation of the brain and muscles.
An overdose can also cause the heart to stop and death. Ketamine is also
known for being more psychologically addictive than most psychedelics and
it is not uncommon to hear of users who take it once or more daily.
Long-term effectsKetamine has the potential to be both physically and
psychologically addicting. Individuals who use it regularly may find it difficult
to stop.
Effects on pregnancy
In humans, safety in pregnancy and lactation has not been established.
However, studies with rats showed that ketamine, PCP (phencyclidine,
another dissociative anesthetics having similar effects as ketamine), and
alcohol trigger widespread cell death in the brains of developing rats.
(For details see:
http://www.drugabuse.gov/NIDA_Notes/NNVol15N2/Ketamine.html)
Treatment
Little is known conclusively about the treatment of ketamine abuse and
counseling appears to be a useful approach.
References:
1. http://www.nbcd.gov.tw/prop/prop_1-11.asp (Chinese)
2.
3.
http://www.greencross.org.tw/drugabuse/ketamine.htm (Chinese)
http://www.erowid.org/chemicals/ketamine/ketamine.shtml
End of Period 2
42
Teacher Notes for Drug
Abuse
PERIOD THREE
D. Benzodiazepines (Sleeping pills)
The term ‘benzodiazepines’ or ‘sleeping pills’ shall be used, instead of other
clinical terms, to describe different drugs belong to this group.
What are benzodiazepines?
Benzodiazepines are CNS depressants or sedative hypnotic compounds
and they are the most common minor tranquilizers and sleeping pills.
Commonly abused/prescribed benzodiazepines include:
 Valium

Librium
In the following discussion, Valium is used as an example to illustrate the
actions and effects of benzodiazepines.
In Hong Kong, unscrupulous medical practitioners, drug store operators and
medicine brokers supply most of the benzodiazepines and related drugs in
the black market.
Street/Other namesIn Hong Kong’s black market, there are about 100

different types of benzodiazepines and related pills that come in
different forms and colours.
Slang terms for this group include Roach, Roofies, Run-Trip-and-Fall,
R-2, Mexican Valium, Rohypnol, Rib, and Rope.
[Surf the web to download their pictures.]
Clinical uses
 Valium is used as a sedative and anti-anxiety agent and taken orally.
How is it abused?
Most of the drugs in this group are colorless, odorless and flavorless; they
can be slipped into drinks unnoticed. This is one reason why these drugs are
so dangerous. People may consume it without knowing it. It dissolves
quickly and takes effect in 20-30 minutes.
43
Teacher Notes for Drug
Abuse
How does it exert its effects?
Valium influences behavior by interacting with receptors on neurons in the
brain that use the neurotransmitter called GABA. When GABA binds to
receptors, it usually inhibits a neuron and acts to reduce neuronal activity.
When benzodiazepines attach to GABA receptors, they increase GABA
binding to other receptors. In this way, benzodiazepines enhance the
inhibitory effects of GABA and reduce brain activity.
Short-term effects
At low doses (doses prescribed by a doctor), Valium acts as a sedative and
reduce psychomotor responses, anxiety; reduce respiration, reduce blood
pressure, reduce heart rate and induce sleep.
At high doses, Valium can actually increase some types of behavior and act
like a stimulant. These effects are caused by depression of inhibitory brain
circuits. In other words, they can produce amnesia (memory loss) and
muscle relaxation and make people lower their inhibitions. [An inhibition is
when you feel like you can't do something. When inhibitions are lowered,
people feel as if an obstacle has been removed. Therefore, they can talk
more freely and feel less shy.]
Overdoses of Valium can lead to excessive sedation and cause anesthesia,
coma and even death. Overdoses may occur because the effective dose of
these drugs is not too far away from the lethal dose.
Long-term effects:
Long-term uses of large doses of Valium can lead to addiction. This is
because both may lead to tolerance and dependence.
What are ’tolerance’ and ‘ dependence’?
Tolerance occurs when a greater and greater amount of the drug is required
to get the desired effect. For example, if a large dose of Valium is used to
help a person sleep, over time, a greater dose of the drug will be needed to
get the person to sleep.
Dependence occurs when a person feels like he or she must use the drug
and withdrawal symptoms occur when the person stops using the drug.
44
Teacher Notes for Drug
Abuse
Withdrawal symptoms of Valium addiction:





Headache
Muscle pain
Confusion
Hallucinations
Convulsions
Valium, when taken along with other drugs (in particular heroin) or alcohol, is
a common cause of overdose toxicity and overdose related deaths.
Effects of pregnancy
Long-term use of Valium in large dose is addictive to both the mother and
the baby. The baby is less able to cope with this type of drug than the
mother. It is recommended that the use of Valium and other depressants be
avoided during pregnancy, as they can be harmful if taken continuously or in
high doses.
Valium and other depressants can produce withdrawal symptoms in
newborn babies.
Withdrawal symptoms of newborn babies include:




Breathing problems
Poor body temperature control
Poor muscle tone
Difficult sucking
The babies can appear floppy or limp and this poor muscle tone can last for
a number of months, although the babies do eventually recover.
TreatmentThere is no effective medical treatment for abuse of
benzodiazepines and the most effective treatment is counseling.
References:
http://faculty.washington.edu/chudler/barb.html
http://faculty.washington.edu/chudler/roof.html Teacher Notes for Drug
http://www.hon.ch/Dossier/MotherChild/preg_drugs/benzodiazepines.html
Abuse
http://womenshealth.about.com/library/bldaterapedrugfaq.htm?terms=Treat
ment+Rohypnol
45
E. GHB
(Slides 49-51)
What is GHB?
Gamma-hydroxybutyrate (GHB) [G 水、迷暈水] is both a metabolite and
precursor of the nhibitory neurotransmitter GABA (gamma-aminobutyric
acid, or gamma-aminobutyrate). It is a naturally occurring component of
human cells. GHB is a constituent of some wine, and it has been speculated
that GHB may be responsible for the soporific (a substance causing sleep)
effects of wine.
Street/Other names
GHB, G, Liquid X, Liquid E, GBH, Gamma-oh, Blue Verve, G 水, 迷暈水, etc
It is called a “date rape drug” because it is believed to improve sex
performance, but this is arguable.
Clinical uses
GHB was developed in the early 60s as an anaesthetic, but was
discontinued due to unwanted side effects. [It was used in Europe as a
general anesthetic, a treatment for insomnia and narcolepsy (a daytime
sleeping disorder), an aid to childbirth (increasing strength of contractions,
decreasing pain, and increasing dilation of the cervix) and a treatment for
alcoholism and alcohol withdrawal syndrome.]
During the 1980s, GHB was widely available over-the-counter in health-food
stores, purchased largely by body-builders for its ability to stimulate growth
hormone release which aids in fat reduction and muscle building. [Reason:
Contributing to anabolism and breakdown of fat in our body, GHB activates a
metabolic process known as the "pentose pathway" which plays an
important role in the synthesis of protein within the body. It also causes a
"protein sparing" effect which reduces the rate at which the body breaks
down its own proteins. These properties, along with GHB's effect on growth
hormone, underlie its common use as an aid to muscle-building and fat loss.]
46
Teacher Notes for Drug
Abuse
Helping to reduce body cortisol levels. Cortisol is a steroid hormone that
stimulates the breakdown of proteins. (It is therefore called “anti-catabolic”.)
One of the major concerns with GHB is that the recreational dosage range is
narrow and even small overdoses can cause temporary unrousable
unconsciousness (a type of coma) and large overdoses (poisonings) can be
life threatening.
GHB was banned from over-the-counter sale by the Food and Drug
Administration, USA in 1990, and it is illegal to possess this drug in Hong
Kong.
How is it abused?
GHB commonly comes as a colorless, odorless, bitter or salty-tasting liquid
usually sold in the black market in small bottles or vials. It also comes as a
crystal powder. It is mostly taken orally, however, there have been reports of
people injecting the drug.
How does it exert its effects?
GHB has a structure similar to that of neurotransmitter GABA
(gamma-aminobutyric acid), however, does not act directly on GABA
receptor sites.
In animals GHB induces "sleep", and in humans it was used as a general
anesthetic in surgical procedures. The mechanism of action of GHB is still
unclear. One study suggests that at the cellular level GHB can inhibit
neuronal activity. EEG recordings have revealed that the administration of
GHB can lead to episodes of epilepsy.
(For detail visit: http://www.medlib.iupui.edu/ecme/gofflab3.htm)
Short-term effects:
Effects of lower amounts may include:
 Sense of well-being and relaxation
 Increased confidence and sociability
 Enhanced sense of touch
 Drowsiness, induced sleep, nausea, dizziness, and headache
47
Teacher Notes for Drug
Abuse
An increase in the amount or strength of GHB used, may result in the initial
feelings of euphoria being replaced by effects including:
 Impaired movement and speech
 Extreme drowsiness
 Hallucinations
 Difficulty focusing eyes
 Vomiting and convulsions
 Disorientation


Respiratory collapse  unconsciousness
Amnesia (afterwards)
Whatever side effects may be noted, they are often much more severe when
GHB is combined with other depressants such as alcohol, ketamine, heroin
and Valium (a sleeping pills), as these drugs affect different brain areas and
they help to further suppress respiration. For example, adding alcohol on top
of GHB will highly and rapidly increase the possibility of respiratory collapse,
coma and possibly death.
The effects of GHB can generally be felt within five to twenty minutes after
ingestion. Determining the ideal dose is probably the trickiest aspect of
abusing GHB. The amount required for a given level of effect will vary from
person to person, and the dose-response curve is fairly steep.
After excessive use, some users have experienced seizures and coma. The
amount used to feel its effect, the amount needed for anesthesia effects and
the amount that can cause seizures or comas are very close. So, abuse of
GHB is extremely dangerous.
Because GHB generally comes in liquid form and thus the concentration is
difficult to determine, thus, there is a real danger of overdose toxicity.
Long-term effects
There has been little research conducted on the effects of long-term use of
GHB. Apart from the potential to develop physical and psychological
dependence, the health and social consequences of long-term use are
largely unknown.
48
Teacher Notes for Drug
Abuse
The addiction potential of GHB is not well known, but from reports it appears
that GHB can be both physically addicting and mentally habituating for a
small percentage of users. Withdrawal symptoms include a strong desire to
take GHB or other psychotropic substances, difficulty sleeping, vertigo, and
worrisome chest pains.
Effects on pregnancy
Little is known about GHB use during pregnancy. As is the case with many
other licit and illicit drugs, GHB use during pregnancy is not recommended.
Drug use during pregnancy can increase the incidence of premature labour,
resulting in low birth weight babies. If the mother continues to use GHB while
breastfeeding, it is possible that the drug will be present in the mother's milk
and possibly cause adverse affects to the baby.
Treatment
There is no effective medical treatment for GHB abuse and counseling is the
method of choice.
References:
http://www.adf.org.au/drughit/facts/ghb.html
http://www.ceida.net.au/tools_for_workers/drugs/ghb.htm
http://www.emedicine.com/emerg/topic848.htm
Stimulants
(Slide 52)
What are stimulants?
CNS stimulants are chemicals that can increase the activities of the brain
Types of stimulants
(Slide 53)
In here, stimulants are divided into two types: socially accepted (caffeine and
nicotine) and unaccepted (amphetamines and cocaine). The examples are
commonly used or abused drugs/chemicals.
[Note that the division is based on mechanisms of action of these
drugs/chemicals.]
49
Teacher Notes for Drug
Abuse
Other CNS stimulants also include:
1. Antidepressants are used to treat patients suffering from depression, a
psychiatric disease,
2. Convulsants (seizure-inducing drugs) which include strychnine
(strych-nine) and picrotoxin, both are not/rarely used clinically nowadays.
Strychnine was used as a stomachic, an antidote for depressant poisons,
etc. It can produce acute or chronic poisoning in humans or animals.
Picrotoxin is the “bitter poison” found in the berries of an Indonesian plant
(Anamirta cocculus). The crushed berries thrown into the water poisoned
fish and allowed them to be gathered.
A. Caffeine
(Slide 54)
Caffeine-containing beverages are used habitually in different cultures.
Fox example, Chinese, Japanese, Indians and Britain have the habit of
drinking tea while South and North Americans drink coffee. In Hong Kong,
many people, young and old, like to drink Pepsi Cola, Coca Cola and other
cola drinks.
[According to one of the Internet sites (http://ask.yahoo.com/19991108.html)
measuring caffeine by “caffeine index”, coffee has the most caffeine with
47-164 milligrams per 150 milliliter (mL) serving. The caffeine content
depends on how the coffee is brewed -- fresh drip has the highest level,
instant has the lowest. Caffeine-free coffer contains about 3-6 mg per cup.
Second place is a little more difficult to determine. A single serving of black
tea (150 mL) can have anywhere from 25 to 110 milligrams of caffeine, while
a single serving of Coca-Cola (350 mL) measures in with 46 milligrams.
However, when you break it down to caffeine per mL, tea handily beats
Coke.]
Chocolates also contain caffeine because they contain cocoa (dark brown
powder make from crushed cocoa seeds).
(Visit http://ask.yahoo.com/ask/20001018.html to find out how much caffeine
in chocolates.)
50
The various effects of caffeine are given below:
1. Slightly  pulse rate (1 cup/day).
2. Alertness and Fatigue (1 cup or more).
3.  Loss of calcium in the urine (5 cups/day). [Caffeine increases water
excretion.]
4. A possible human teratogen (>6 mg/kg body weight). [A teratogen is a
chemical that causes abnormal fetus development.]
5.  Calorie intake. [This is because most of these drinks contain sugar.]
6. Affects sleep patterns
7. Withdrawal symptoms: Headaches, gastrointestinal effects and diarrhea.
B. Nicotine (Tobacco smoking)
(Slide 55)
Apart from caffeine, nicotine is the most widely used stimulant in our society.
Nicotine is an alkaloid found in tobacco.
Comments on the effects
Nicotine is an extremely potent stimulant exerting powerful effects on the
brain, the spinal cord the peripheral nervous system, the heart and various
other body structures. It exerts its various effects by stimulating acetylcholine
receptors that are widely distributed in our bodies. [Acetylcholine is a
neurotransmitter.]
Chronic smoking results in a smoker’s syndrome characterized by difficulty
in breathing, wheezing, chest pain lung congestion and increasing
susceptibility to infections of the respiratory tract.
Cigarette smoking impairs ventilation and greatly increases the risk of
emphysema (a form of irreversible lung damage).
There is a strong correlation between smoking and lung cancer. However,
lung cancer is believed to be caused by tars and other chemicals in tobacco
rather than nicotine.
There is also evidence that smoking has harmful effects on the developing
foetus. Cigarette smoking increases the rates of spontaneous abortion,
stillbirths and early postpartum death of infants. Thus, pregnant women are
advised to quit smoking.
51
Teacher Notes for Drug
Abuse
Nicotine was at one time used as an insecticide. [This is because nicotine
can interfere with insect movements, e.g. flight, breathing, etc, by stimulating
acetylcholine receptors in the brain, spinal cord, skeletal muscles including
the contraction and relaxation of the diaphragm. Newer insecticides have
now replaced it. Some of the newer insecticides are acetylcholine esterase
(an enzyme which degrades acetylcholine) inhibitors. These insecticides
increase/prolong the effect of acetylcholine.]
C. Amphetamine and related compounds
(Slides 56-58)
What are they?
This group includes amphetamine: methylene dioxymethamphetamine
(MDMA, ecstasy) and methamphetamine (Ice). They have chemical
structures similar to those of amphetamine, and they act as stimulants in the
nervous system. Stimulants can create a sense of well-being and higher
energy, sometimes a release of social inhibition, and feelings of
“cleverness”, “competence” and “power”. But these are unreal. They are
popular rave party or club drugs in Hong Kong and elsewhere. Because ‘Ice’
is odorless and has a colorless smoke, users of the drug may go virtually
unnoticed. Significant abuse of the drug began to be seen in the United
States in the 1960s and in Hong Kong since the late 1990s.
Street/Other names
Methamphetamine (Ice) or Dextroamphetamine is also known as “Meth”,
‘crystal meth’, ‘speed’, ‘ice’, ‘black beauties’, ‘bennies’, ‘dexies’, ‘beans’,
‘crank’, etc.
“Ice" is a concentrated form of methamphetamine that resembles tiny chunks
of translucent glass (it is also called ‘glass’. It is very potent crystal
methamphetamine in a form that can be "smoked" rather than injected.
Because the “Ice” is vaporized and inhaled, and not actually burned, the
term "smoking" is technically incorrect.
Another very popular synthetic amphetamine is ecstasy, commonly known
as MDMA, short for methylene dioxymethamphetamine. It acts
simultaneously as a stimulant and a hallucinogen. Users sometimes take
ecstasy for the sense of well-being, the sensory distortions caused by the
52
Teacher Notes for Drug
Abuse
drug, or to stay awake. [One of the primary problems with MDMA is the low
quality of street ecstasy. Street ecstasy, especially pressed pills, is often
mixed with a wide variety of adulterants that can cause a variety of negative
side effects both unpleasant and dangerous.]
Herbal ecstasy is a drug composed of ephedrine (ma huang) or
pseudoephedrine and caffeine (kola nut), stimulants that closely simulate the
effects of ecstasy. Sold in tablet form, herbal ecstasy is known as Cloud 9,
Herbal Bliss, Ritual Spirit, Herbal X, GWM, Rave Energy, Ultimate Xphoria,
and X in the US. There is no quality control over the manufacture of these
products, and problems arise because the amounts of ephedrine and
caffeine in the pills vary widely.
Clinical uses
Amphetamines first were synthesized in 1887, but were not used medically
until about 1930. Between 1930 and the early 1960s, amphetamines were
used to treat childhood hyperactivity, obesity and narcolepsy (day sleep), a
rare disorder in which persons are overcome by sudden attacks of deep
sleep.
How is it abused?
Ecstasy is most often found in tablet, capsule, or powder form and is usually
consumed orally, although it can also be injected. Other amphetamine drugs
are used in similar manner. Ecstasy is sometimes packaged in capsules or
generic tablets to imitate prescription drugs.
(For other details see:
http://parentingteens.about.com/library/fs/blsldicamph.htm?terms=Ampheta
mine+.)
Ice is usually consumed by smoking or orally.
How do they exert their effects?
Brain imaging research in humans indicates that all amphetamines cause
injury to the brain, affecting neurons that use the chemicals
(neurotransmitters) serotonin and dopamine to communicate with other
neurons. They do so by releasing more of these neurotransmitters in the
synapses.
53
Teacher Notes for Drug
Abuse
The serotonin system in the brain plays a direct role in regulating mood,
aggression, sexual activity, sleep, and sensitivity to pain. The dopamine
system plays a direct role in controlling mood and movements.
Derangements of dopamine system may cause schizophrenia and
Parkinson’s disease. Many of the risks users face with MDMA and Ice use
are similar to those found with the use of cocaine.
Short-term effects
Physical effects:
 Loss of appetite
 Involuntary teeth clenching





Blurred vision
Increased heart rate and blood pressure
Chills and sweating
Tremors
Deaths have occurred because users don’t drink enough water and
become overheated.
Psychological difficulties can include the following symptoms:
 Confusion
 Depression




Sleep problems
Drug craving (an addiction behaviour)
Severe anxiety
Paranoia - during and sometimes weeks after taking MDMA.
Amphetamine-induced psychosis is a paranoid state that may develop after
ingestion or the injection of large doses of amphetamines.
Long-term effects
Research links MDMA use to long-term damage to those parts of the brain
critical to thought and memory possibly by destroying serotonin-producing
neurons in the brain and causing degeneration of neurons containing the
neurotransmitter dopamine. [Damage to these neurons is the underlying
cause of the motor disturbances seen in Parkinson's disease. Symptoms of
this disease begin with lack of coordination and tremors and can eventually
result in a form of paralysis.]
54
Long-term heavy use
of
Teacher Notes for Drug
Abuse
amphetamines may lead to malnutrition
(amphetamine reduces appetite), skin disorders, ulcers and diseases
resulting from vitamin deficiencies. Regular use may contribute to lack of
sleep and weight loss. Intravenous users are at risk for serious,
life-threatening diseases such as AIDS, lung and heart disease and other
cardiovascular diseases. Frequent use of large amounts of amphetamines
may eventually result in mental illness, suicide or violent death.
Effects on pregnancy
 Pregnant women who take ecstasy, ice and other
amphetamine-related drugs may increase the chances of their
babies developing birth defects.
(For details see http://news.bbc.co.uk/1/hi/health/481775.stm
http://mdma.net/prenatal/pregnancy.html)
and
 Pregnant women who take ecstasy increase their risk of an
abnormal baby by up to seven times.
(For details see:
http://www.erowid.org/chemicals/mdma/references/journal/1999_mcelh
atton_lancet_1/1999_mcelhatton_lancet_1_media1.shtml.)
Treatment
There is no effective medical treatment for abuse of amphetamines and
counseling appears to be a very useful mean.
References:
http://substanceabuse.about.com/library/weekly/aa040700.htm (kills brain
cell)
http://substanceabuse.about.com/library/weekly/aa040700.htm
http://www.nida.nih.gov/infofax/ecstasy.html
http://drugabuse.gov/ResearchReports/methamph/methamph.html
http://www.erowid.org/chemicals/mdma/references/journal/1999_mcelhatton
lancet_1/1999_mcelhatton_lancet_1_media1.shtml
http://faculty.washington.edu/chudler/mdma.html
http://weber.Im.flu.edu.tw/~swduh/sociology_of_drug/amphetamine_1.htm
(Chinese)
http://www.greencross.org.tw/drugabuse/amph_withdraw.htm (Chinese)
55
Teacher Notes for Drug
Abuse
D. Cocaine
(Slides 59-61)
General information
Cocaine, a stimulant, is one of the most addictive psychotropic substances.
The other is heroin.
It is one of the oldest known drugs. The pure chemical, cocaine
hydrochloride, has been an abused substance for more than 100 years, and
coca leaves, the source of cocaine, have been ingested for thousands of
years particularly in South American countries for example, Peru and Bolivia.
It was used as tonics/elixirs to treat a wide variety of illnesses. Because of its
powerful addictive effect, this usage has been abandoned.
The major sources of cocaine are some South American countries. There
are two chemical forms of cocaine: the hydrochloride salt and the "freebase“
(not neutralized by an acid). The hydrochloride salt, or powdered form of
cocaine, dissolves in water and, when abused, can be taken intravenously
(by injection) or intranasally (sniffing). The freebase form of cocaine is
smokable.
Street names or other names
Cocaine is generally sold on the street as a fine, white, crystalline powder,
known as "coke," "C," "snow," "flake," or "blow."
The term "crack" refers to the crackling sound heard when the mixture is
smoked.
Street dealers generally dilute it with such inert substances such as corn
starch, talcum powder, and/or sugar, or with such active drugs like procaine
(a local anesthetic) or with such other stimulants such as amphetamines.
Cocaine abuse and addiction continues to be a major problem in Europe and
North and South Americas. For example, an estimated 1.5 million Americans
age 12 and older were chronic cocaine users in 1997. However, the number
of cocaine abusers in Hong Kong remains small. One reason may be
because cocaine in the local black market is very expensive.
56
Teacher Notes for Drug
Abuse
How does cocaine exert its effects in the brain?
It does so by preventing the re-absorption of dopamine (a neurotransmitter)
in nerve terminals.
For details see:
http://www.drugabuse.gov/ResearchReports/Cocaine/cocaine3.html#effects”
[Through the use of sophisticated technology (positron emission tomography
scanning, also called a PET scan), scientists can actually see the dynamic
changes that occur in the brain as an individual takes the drug. They can
observe the different brain changes that occur as a person experiences the
"rush," the "high," and, finally, the craving of cocaine. They can also identify
parts of the brain that become active when a cocaine addict sees or hears
environmental stimuli that trigger the craving for cocaine. Because these
types of studies pinpoint specific brain regions, they are critical to identifying
targets for developing medications to treat cocaine addiction.]
Short-term effects
Cocaine's effects appear almost immediately after a single dose, and
disappear within a few minutes or hours.
In small amounts (up to 100 mg), cocaine usually makes the user feel
euphoric, energetic, talkative, and mentally alert, especially to the sensations
of sight, sound, and touch. (These are common effects of CNS stimulants) It
can also temporarily decrease the need for food and sleep.
Some users find that the drug helps them to perform simple physical and
intellectual tasks more quickly, while others can experience the opposite
effect.
The short-term physiological effects of cocaine include:



Dilated pupils
Increased body heat sensation
Increased heart rate and blood pressure (constricted blood
vessels).
In large amounts (several hundred milligrams or more) intensify the user's
high, but may also lead to bizarre, erratic, and violent behavior. These users
may experience tremors, vertigo, muscle twitches, paranoia, or, with
57
Teacher Notes for Drug
repeated doses, a toxic reaction closely resembling
Abuseamphetamine poisoning.
Some users of cocaine report feelings of restlessness, irritability, and
anxiety.
In rare instances, sudden death can occur on the first use of cocaine or
unexpectedly thereafter. Cocaine-related deaths are often a result of cardiac
arrest or seizures followed by respiratory arrest.
Long-term effects
Cocaine is a powerfully addictive drug. Once having tried cocaine, an
individual may have difficulty predicting or controlling the extent to which he
or she will continue to use the drug.
Cocaine's stimulant and addictive effects are thought to be primarily a result
of its ability to inhibit the re-absorption of dopamine by nerve cells.
Dopamine is released as part of the brain's reward system, and is either
directly or indirectly involved in the addictive properties of every major drug
of abuse.
An appreciable tolerance to cocaine's high may develop, with many addicts
reporting that they seek but fail to achieve as much pleasure as they did
from their first experience. Some users will frequently increase their doses to
intensify and prolong the euphoric effects.
While tolerance to the high can occur, users can also become more
sensitive (sensitization) to cocaine's anesthetic and convulsant effects,
without increasing the dose taken. This increased sensitivity may explain
some deaths occurring after apparently low doses of cocaine.
Use of cocaine in a binge, during which the drug is taken repeatedly and at
increasingly high doses, leads to a state of increasing irritability,
restlessness, and paranoia. This may result in a full-blown paranoid
psychosis (a mental condition), in which the individual loses touch with
reality and experiences auditory hallucinations.
Reference:
http://www.drugabuse.gov/ResearchReports/Cocaine/cocaine2.html#what
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Effects and danger of taking multi-drugs
(Slides 62-64)
A Do not take psychoactive drugs together with alcohol!
The brain compartment is separated from the circulatory (blood) system
by a filter, called the blood-brain barrier. [This protects the brain from
sudden changes in chemical composition in the blood, for example after
a meal.] This filter prevents most substances from entering the brain
freely. To compensate this ‘defect’, there are specialized carrier system
to carry substances, e.g., glucose (a must fuel for the brain) and others,
into the brain to allow the brain to perform its normal functions.
Interestingly, fat-soluble substances do not have to enter the brain by
carriers and they do so by diffusion because they can dissolve in the lipid
components of a cell membrane then enter a cell.
Most, if not all, psychoactive drugs are fat-soluble substances and they
dissolve readily in alcohol (a good solvent for fat-soluble substances), so
these mood-altering drugs can pass through the blood brain barrier more
rapidly by diffusion. Thus, taking these drugs with alcohol would cause a
sudden and sharp rise of the drug(s) in the brain. This may cause
overdose toxicity in the brain and explains why taking psychoactive drugs
with alcohol is extremely dangerous.
The point to be remembered is “Do not use drugs with alcohol!”
B Effects of taking multi-drugs are unpredictable!
Some abusers believe that taking a depressant together with a stimulant
will cancel out each other’s effects. This is Wrong! It is a misconception.
The real answer could be ‘fatal’.
This false belief was developed simply because some abusers think
depressants equate to ‘minuses’, while stimulants ‘pluses’, and they have
the false belief that (-1) + (+1) should equal to 0 (zero) mathematically,
therefore the false belief that taking both together should have no harmful
effect(s).
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This is wrong, of course because:
1.
2.
3.
Depressants and stimulants are very different drugs and they affect
different neurotransmitter systems.
They affect different areas of the brain. [At the beginning of this block,
we discussed the concept that different brain areas perform different
functions.
The fact is taking different kinds of psychoactive drugs together could
be fatal. This is because more neuronal systems and more brain areas
are affected at the same time.
End of Period 3
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PERIOD FOUR
Lead questions related to hallucinogens and materials to be discussed in
this period.
(Slide 66)
Hallucinogens
(Slides 67-70)
What are hallucinogens?
Hallucinogens are also called ‘psychedelics’. They are substances that
induce sensory (vision, sound, smell, etc.) sensitivities of the brain. Under
the influence of hallucinogens, people see images, hear sounds, and feel
sensations that seem real but do not exist. These are called ‘psychedelic’
sensations. These drugs can disrupt a person's ability to think and
communicate rationally, or even to recognize reality, sometimes resulting in
bizarre or dangerous behavior.
The two commonly abused hallucinogens in HK are LSD and marijuana.
[Note that although ketamine is classified as a depressant in this block, it
can distort perceptions of sight and sound and produces feelings of
detachment - dissociation - from the environment and self. The details of
ketamine will not be repeated here.]
A. LSD
What is LSD?
Lysergic acid diethylamide (LSD) is a hallucinogen that causes emotions to
swing wildly and from real-world sensations to assume unreal, sometimes
frightening aspects.
LSD is the hallucinogen most widely used in this class of drugs. Recently,
LSD and ketamine are becoming more widely used at entertainment places
and all-night rave parties by older teens and young adults in Hong Kong.
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Herbal hallucinogens
In addition to LSD and marijuana, there are other hallucinogens, in the forms
of hallucinogenic plants that had been used in many cultures. These plants
contain chemical compounds, such as mescaline, psilocybin and
ibogaine.
Mescaline is obtained from cactus of 2-5 inches in diameter, which grow in
Mexico and the Southwest United States.
Psilocybin can be obtained from some so called 'magic mushrooms'
belonging primarily to the geniuses Psilocybe, Panaeolus, and Copelandia.
Nearly all of the psilocybin-containing mushrooms are small brown or tan
mushrooms easily mistakable for any number of non-psychoactive, inedible,
or poisonous mushrooms in the wild.
Ibogaine can be obtained from the root/root bark of Tabernanthe iboga or
Trachelospermum jasminoides (Star Jasmine).
Of this group, however, LSD is by far the most potent; it is approximately
100 times stronger than psilocybin and 4,000 times stronger than mescaline.
The effects of their ingestion resemble a shorter acting LSD trip, producing
significant physical, visual, and perceptual changes. Abuse of these plant
hallucinogens is not common in HK, probably because of lack of supply.
History of LSD
LSD was synthesized in 1938 by German chemist Albert Hofmann. He
discovered LSD when he was conducting research on possible medical
applications of various lysergic acid compounds derived from ergot, a fungus
that develops on rye grass. Later, he accidentally ingested a small amount
and experienced a series of frightening sensory effects, and he wrote: "My
surroundings . . . transformed themselves in more terrifying ways. Everything
in the room spun around, and the familiar objects and pieces of furniture
assumed grotesque, threatening forms. They were in continuous motion,
animated, as if driven by an inner restlessness. Even worse than these
demonic transformations of the outer world were the alterations that I
perceived in myself, in my inner being. Every exertion of my will, every
attempt to put an end to the disintegration of the outer world and the
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dissolution of my ego, seemed to be wasted effort. A demon had invaded
me, had taken possession of my body, mind, and soul."
For details see:
http://www.drugabuse.gov/ResearchReports/Hallucinogens/halluc3.html.
Properties of LSD
LSD is a clear or white, odorless, water-soluble material synthesized from
lysergic acid, a compound derived from a rye fungus. LSD is the most
potent mood- and perception-altering drug known: oral doses as small as 30
micrograms (mg) can produce effects that last 6 to 12 hours.
The most common form of LSD is called "blotter acid" - sheets of blotting
paper soaked in LSD. Drug distributors often apply LSD to colored paper,
making it difficult for a buyer to determine the drug's purity or dosage. (Purity
of this street drug is an issue of concern in substance abuse.)
Street/Other names
Acid, angel dust, and vitamin K
Clinical uses
Most hallucinogens, including LSD, which are intended for illegal uses, have
no accepted medical use.
How is it used?
LSD is usually taken orally, but is sometimes inhaled or injected.
How does it exert its effects?
LSD, which has a chemical structure similar to serotonin, causes its effects
by disrupting the interaction of nerve cells using serotonin as the
neurotransmitter. Nerves use serotonin are distributed throughout the brain
and spinal cord, and the serotonin system is involved in the control of
behavioral, perceptual, and regulatory systems, including mood, hunger,
body temperature, sexual behavior, muscle control, and sensory perception.
[The precise mechanism by which LSD alters perceptions is still unclear.
Evidence from laboratory studies suggests that LSD, like hallucinogenic
plants, acts on certain groups of serotonin receptors, and that its effects are
most prominent in two brain regions: one is the cerebral cortex, an area
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Teacher Notes for Drug
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involved in mood, cognition, and perception; the other is the brain stem, the
brain’s detector for external stimuli, which receives sensory signals from all
areas of the body.]
Short-term effects
Short-term effects appear soon after a single dose and disappear within a
few hours or days.
Physical effects include:
 Increased blood pressure and heart rate
 Increased temperature and sweating




Impaired motor skills and coordination
Nausea; dizziness, loss of appetite
Dry mouth
Affect emotion and sensory (major effects of hallucinogens)
After the physical effects, dramatic changes in perception, thought, and
mood occur. These may include:
 Vivid, usually visual, "pseudo-hallucinations" that the user is aware
are not real.
 Distorted perceptions of: time (minutes seem like hours)



Distorted distance perception (hazardous if operating motor vehicles
or standing near balcony edges)
Space between oneself and one's environment (for some, a feeling of
oneness with the universe, for others, a feeling of terror)
Fusion of the senses (music is “seen,” colors “heard”) is experienced.
[Users refer to LSD and other hallucinogenic experiences as "trips" and to
the acute adverse experiences as "bad trips." On some trips, users
experience sensations that are enjoyable and mentally stimulating and that
produce a sense of heightened understanding. Bad trips, however, include
terrifying thoughts and nightmarish feelings of anxiety and despair that
include fears of insanity, death, or losing control. Although most LSD trips
include both pleasant and unpleasant aspects, the drug's effects are
unpredictable and may vary with the amount ingested and the user's
personality, mood, expectations, and surroundings.]
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Long-term effects
LSD users quickly develop a high degree of tolerance for the drug's effects.
After repeated use, they need increasingly larger doses to produce similar
effects. This may result in addiction.
Two long-term effects persistent psychosis and hallucinogen persisting
perception disorder, more commonly referred to as "flashbacks"-have been
associated with use of LSD. The causes of these effects, which in some
users occur after a single experience with the drug, are not known.
Psychosis is the disorganization of a person's capacity to recognize reality,
think rationally, or communicate with others. These effects of LSD may last
for years and can affect people who have no history or other symptoms of
psychological disorder.
Hallucinogen Persisting Perception Disorder consists of episodes of
spontaneous, repeated, sometimes continuous recurrences of some of the
sensory distortions originally produced by LSD. The experience may include
hallucinations, but it most commonly consists of visual disturbances such as
seeing false motion on the edges of the field of vision, bright or colored
flashes, and halos or trails attached to moving objects. This condition is
typically persistent and in some cases remains unchanged for years after
individuals have stopped using the drug. Chronic LSD use may result in
prolonged depression and anxiety.
Effects on pregnancy
There appears to be a higher risk of spontaneous abortion and congenital
abnormalities in babies born to women who regularly used LSD during
pregnancy. [But in almost all such cases reviewed, the mothers had also
taken other drugs during pregnancy; it is thus difficult to determine how
much each drug contributed to the problems.]
There have been a number of good recent investigations of the effect of
hallucinogenic drugs on developing embryos in rodents. A group of scientists
compared the effect of LSD injected in rats both early and late in pregnancy
with the effect of injecting only saline solution. While they found that there
were no apparent effects of LSD on offspring when given late in the mother's
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Teacher Notes for Drug
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pregnancy, there were substantially more stunted and stillborn offspring from
the mothers who had received LSD early in pregnancy.
Another group performed a similar experiment, this time with mice.
Examining the embryos four days after administering a drug to the mothers,
they found that there were substantially more embryological abnormalities
from the mothers who had been injected with LSD early in pregnancy than in
mothers who had been injected during the same period with a control
substance or who had not been injected at all. However, there were no gross
observable effects when injections were given late in pregnancy.
It appears that there is at present no adequate evidence that hallucinogenic
drugs in ‘ordinary doses’ cause chromosomal damage in the living organism
or adversely affect offspring as a result of chromosomal changes.
For details see:
http://www.erowid.org/psychoactives/pregnancy/pregnancy_journal1.shtml
Treatment
There is no effective medical treatment for LSD abuse, and counseling
appears to be the method of choice.
References:
http://www.drugabuse.gov/ResearchReports/Hallucinogens/hallucinogens.ht
mlhttp://www.erowid.org/plants/peyote/peyote.shtml (Mescaline/peyote)
http://www.erowid.org/plants/mushrooms/mushrooms.shtml (Psilocybin and
magic or hallucinogenic mushrooms)
http://www.erowid.org/chemicals/ibogaine/ibogaine.shtml (Ibogaine)
B. Marijuana
Slides (71-73)
What is marijuana?
Marijuana (Marihuana) is a green, brown or grey mixture of dried, shredded
leaves, stems, seeds and flowers of the hemp plant (Cannabis sativa). It is a
mind-altering substance.
[Puzzle: Do hemp seeds (火麻仁) contain active ingredients of marijuana?
The answer is no. Hemp seeds contains very little amount, if any, of active
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Teacher Notes for Drug
Abuse
hallucinogenic ingredients. Also, all hemp seeds obtainable from local
Chinese herbal stores have been heat-treated, so they are ‘dead’ seeds.].
Street/Other names
Pot’, ‘herb’, ‘weed grass’, ‘boom’, ‘Mary Jane’, ‘gangster or chronic’, ’grass’
and hashish (‘hash’ for short). Hashish is the stronger form of marijuana.
Clinical uses
Marijuana in its smoked form has no commonly accepted medical use. THC
(delta-9-tetrahydrocannabinol; te-tra-hydro-can-na-bin-nol), the active
ingredient in marijuana, has been used by some medical practitioners to
treat nausea and vomiting that occur with certain cancer treatments and to
help AIDS patients eat more to keep up their weight. However, further
studies are needed to determine its therapeutic value and consequence of
regular use.
How is it abused?
Marijuana is usually smoked as a cigarette (called a ‘joint’ or a ‘nail’), or in
pipe.
How does it exert its effects?
All forms of marijuana contain delta-9-tetrahydrocannabinol (THC), the major
active ingredient in marijuana. THC, being very fat-soluble, can be rapidly
absorbed by fat tissues in various organs including the brain. THC exerts its
effects on the brain by binding to THC receptors in nerve cells and the
interaction with THC receptor results in alteration in neurotransmission. The
reason why nerve cells have THC receptors is not very clear.
Short-term effects
Distorted perceptions including sights, sounds, time and touch. This is
because it is a hallucinogen. Other effects are: trouble with thinking and
problem-solving ability, loss of coordination (athletes could find their
performance is off; timing, movements and coordination), and increased
heart rate and anxiety.
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Long-term effects
Tolerance and addiction are common effects.
Marijuana contains some, or even more, of the cancer-causing chemicals,
e.g., tar found in cigarette smoke. [Studies found that someone who smokes
5 joints per week may have taken in as much cancer-causing chemicals as
someone who smokes a full pack of cigarettes every day.]
Thus, long-term marijuana abusers have much higher risk of lung and other
cancers. Development of the same kinds of breathing problems that
cigarette smokers have: coughing and wheezing as well as emphysema.
Animal studies have found that THC can damage cells of the immune
system.
Abusers of marijuana are at higher risk of becoming addicted to other drugs,
such as cocaine and amphetamine-related drugs.
Effects on pregnancy
Marijuana, like other drugs of abuse, can affect a mother's health during
pregnancy, making it a time when expectant mothers should take special
care of themselves. Drugs of abuse may interfere with proper nutrition and
rest, which can affect good functioning of the immune system and have a
detrimental effect on the development of the fetus.
Babies born to marijuana users were shorter, weighed less and had smaller
head sizes. [Head size, or circumference, is an indicator of brain
development during infancy.] Smaller babies are more likely to develop
health problems. Also, Children born to women who abused marijuana
have trouble concentration.
A nursing mother who uses marijuana passes some of the THC to the baby
in her breast milk. Research indicates that the use of marijuana by a mother
during the first month of breast-feeding can impair the infant's motor
development (e.g., control of muscle movement).
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Teacher Notes for Drug
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Treatment
There are currently no medications for treating marijuana addiction
effectively. Treatment programmes focus on counseling and group support
systems are quite effective. See also:
http://www.health.org/reality/articles/2000/youth.asp
References
http://www.nida.nih.gov/MarijNroch/MarijparentsN.htmlhttp://www.nida.nih.go
v/Infofax/marijuana.html
http://www.health.org/reality/articles/2001/birthdefects.asp
Signs of taking club drugs
(Slide 74)
The information given below describes some common observable signs in
club drug abusers.
Signs of drug abuse
1. Problems remembering things they recently said or did (Amnesia)
2. Loss of appetite & ¯ body weightLoss of muscle coordination,
dizziness, fainting
4. Depression
5. Confusion
6. Sleep problems
7. Chills or sweating (for no medical reasons)
8. Slurred speech
The main point is to inform students that drug abuse can be identified, and
that the belief that misuse of club drugs can be hidden is false. So, stay
away from drugs.
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Teacher Notes for Drug
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Some major effects of drug abuse
(Slide 75)
Some major effects of drug abuse
1. Addiction & withdrawal
2. Affects heart, kidney & liver functions
3. Affects brain function by interfering with neuronal transmissionMay
cause death because of:
a. Impurities/toxic substances found in the drug
b. Overdose [Concentrations vary in packages]
c. Poly-drug use [Remember that different drugs affect different brain
areas and different neurotransmitter systems]
Summary of effects of psychoactive drug abuse on different organs
(Slide 76)
The figure below summarizes the effects of different drugs on different
organs in our body. One very important point to be remembered is that these
drugs also affect other vital organs in our body.
Some suggested ways to say “No” to drugs
(Slide 77)
These are some suggested ways to say “No!” to drugs.
Some means to say “No” to drugs
1. Avoid places where drug-uses are likely
2. Keep ‘suspected’ abusers at arm’s length
3. When offered drugs:
a. Say “No” decisively, and tell them the harmful effects of drugs
b. Change the subject or excuse yourself and leave the place
c. Accept the offer, and tell them that you would like showing it to
your teachers/social worker at school/friends
d. Other appropriate means
Can you think of other good ways to refuse drugs?
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Teacher Notes for Drug
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Penalties of drugs-related crimes
(Slide 78)
The figure below summaries the penalty in HK and neighboring places.
The point to be noted is that possession/trafficking of some of these drugs is
illegal and the penalty is very heavy. For example, in Singapore, possession
of 15 grams of heroin can result in the death penalty.
Maximum penalties for drug-related crimes
Places
Penalty
Hong Kong
Life imprisonment and confiscation of properties
Mainland China
Death or life imprisonment and confiscation of properties
Macau
Long prison terms
Singapore
Death (>15 grams of heroin
(Slide 79) – End of Period 4 and this block
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