Download Chapter 16

Chapter 16
Using Drugs Responsibly
What Is a Drug?
• A drug is a chemical in a medicine that affects one
or more of the body’s biological functions.
• Alteration can be to start, stop, speed up, or slow
down a process.
• A medicine is a drug (or combination of drugs)
that is used to prevent illness, cure disease, aid
healing, or suppress symptoms.
• Drugs are classified according to the particular
biological process they affect rather than by their
chemical properties.
Drug Laws
• Drugs are categorized into the following five
groups:
– Prescription drugs
– Over-the-counter drugs
– Dietary supplements
– Addictive drugs
– Illegal drugs
How Drugs Work
• Many drugs act by interacting with specific
cells in the body that carry receptors, which
are proteins on the surface or inside a cell to
which a drug or natural substance can bind
and affect cell function.
• When a drug binds to a receptor, it affects
the biological processes of cells or organs.
How Drugs Work
How Drugs Work
Unintended Harmful Effects of Drugs
• Even though a drug may be intended to have a
single effect, it often does not because it binds to
different kinds of receptors on different cells.
• Unintended drug actions are called side effects.
• Some side effects include allergic reactions called
drug hypersensitivity.
Routes of Drug Administration
• Drugs can be taken:
– By mouth
– By inhalation
– By injection into the muscle or bloodstream
– By implant under the skin
– Through the skin
– Through mucous membranes of the eyes, nose,
vagina, and anus
• Drugs remain active in the body for a relatively
short time, often only a few hours.
Effectiveness of Drugs
• The dose of a drug is the amount that is
administered or taken.
• Effectiveness of a particular dose of a drug is
influenced by:
– Person’s body size
– How rapidly the drug breaks down and is
eliminated
– The presence of other drugs or food in the body
– The person’s mental state
– Person’s expectations of the drug’s efficacy
Effectiveness of Drugs
Psychoactive Drugs
• Psychoactive drugs alter thoughts, feelings,
and sensations.
• Psychoactive drugs include:
– Tranquilizers
– Sleeping pills
– Mood modifiers
Lifestyle Drugs
• Lifestyle drugs are sold to basically healthy
middle-class Americans.
• Lifestyle drugs are used in the place of
making healthy choices such as eating a diet
of vegetables and fruit and staying active.
Drug Company Advertising
• Pharmaceutical companies market to doctors by
“courting” them for business.
• In the United States, pharmaceutical companies
are also allowed to advertise directly to consumers
through television and print media.
The FDA and You
• A number of tests are run on groups of volunteers
to test a drug’s effectiveness.
• Drugs are also watched for side effects.
• Only after trials are done does the FDA give
approval for sale.
Drug Misuse, Abuse, and Addiction
• Using any drug to the point where health
is adversely affected or the ability to function in
society is impaired can be defined as drug abuse.
• Drug abuse refers to the person taking the drug
being personally or socially impaired.
• A drug is being abused if the user cannot control
taking it and the drug is being used continually to
mask anxiety, combat stress, or seek pleasure.
Addiction
• Progressive, chronic, primary disease
characterized by:
– Compulsion
– Loss of control
– Continued drug use despite adverse
consequences
– Distortions in normal thinking
• Physical dependence (tissue dependence) is the
biological adaptation to long-term exposure to a
drug. Both illegal and legal drugs can cause
physical dependence.
Tolerance
• Tolerance is the adaptation of the body to a
drug so that larger doses are needed to
produce the same effect.
• The longer a drug is used, the more of that
drug must be consumed to produce the
desired effect.
Withdrawal
• Withdrawal is a consequence of physical
dependence—withdrawal is experienced
after the drug is no longer used.
• Often it is uncomfortable and it may be
fatal.
• Symptoms are often opposite of the drug’s
primary effects.
Withdrawal
• In general, withdrawal from nervous system
depressants leads to:
– Anxiety
– Irritability
– Susceptibility to seizures
• Withdrawal from stimulants can produce:
– Sleepiness
– Depression
– Loss of consciousness
Psychological Dependence
• Psychological dependence is the habituation
manifested as an intense craving for the
drug.
• Compulsive drug-seeking behavior may
destroy relationships, jobs, and families.
Stimulants
• Substances that increase the activity of the central
nervous system and are referred to as “uppers.”
• Common stimulants include cocaine,
amphetamines, and caffeine.
• Main effects include:
– Increased mental arousal and physical energy
– A state of euphoria
• Long-term use causes physical and psychological
dependence.
Cocaine
• Stimulant obtained from the coca shrub.
• Induces euphoria, sense of power and clarity of
thought, increased physical vigor, increased heart
rate and blood pressure.
• Continued use can result in:
– Loss of appetite and weight loss
– Malnutrition
– Sleep disturbance
– Altered thought and mood patterns
Cocaine
• Frequent cocaine sniffing can damage the nasal
septum.
• Routes of administration:
– Sniffing (“snorting”) it as a white powder
– Injecting it directly into the bloodstream
– Smoking it in the form of “free base” or
“crack”
• Produces tolerance, physical dependence, and
withdrawal.
• Potential for psychological dependence with
cocaine is very high.
Amphetamines
• Manufactured chemicals that stimulate the central
nervous system
• Most common are:
– Dextroamphetamine
– Methamphetamine
– Dextromethamphetamine
– “Ice” is a dangerous form that is smoked.
• Produce a hallucinogenic effect that lasts for hours
Amphetamines
• Usually taken orally, but can be injected
• Can be prescribed by physicians, but have little
medical use
• Produce feelings of euphoria, increased energy,
greater self-confidence, increased ability to
concentrate, increased motor and speech activity,
perceived improvement in physical performance
Amphetamines
• Excessive use can cause:
– Headaches
– Irritability
– Dizziness
– Insomnia
– Panic and confusion
– Delirium
– Crash
– Tolerance
– Mild physical dependence
Caffeine
• Natural substance found in a variety of
plants used in making coffee, tea, chocolate,
and soft drinks
• Produces decreased drowsiness and fatigue,
faster and clearer flow of thought, increased
capacity for sustained performance,
nervousness, tremors, insomnia, and
inability to perform complex tasks
Caffeine
• Psychological dependence can result from chronic
use and tolerance can gradually develop.
• Mild withdrawal symptoms can occur when
caffeine use is ceased, including:
– Headache
– Irritability
– Restlessness
– Lethargy
Club Drugs
• Consist of several psychoactive chemicals that are
often used at social events
• These include:
– Ecstasy
– GHB
– Ketamine
– Rohypnol
Ecstasy
• Methylenedioxymethamphetamine—an
amphetamine that has become popular in recent
years.
• Also called “Ecstasy,” “Adam,” “XTC,” “Clarity,”
“Essence,” MDMA, or MDM.
• Users experience hallucinogenic effects
and euphoria.
• Stimulates the release of serotonin, producing a
high that can last hours.
GHB
• Gamma-hydroxybutyrate
• Also called “G” or “Liquid Ecstasy”
• Causes sedation, increased sexual interest,
relaxation, short-term amnesia
• Very dangerous to mix with alcohol
Ketamine
• Is a dissociative psychedelic used medically
as a veterinary and human anaesthetic.
• Also called “K,” “Special K,” or “Cat
Tranquilizer”
• Causes hallucinations, bizarre behavior,
psychosis
Rohypnol
• Flunitrazepam is a benzodiazepine used as a
sleep medication favored for its short
duration.
• Also called “Ruffies” or “Roofies.”
• Reduces anxiety, inhibition, and muscular
tension.
• Has received a lot of attention as a “date
rape drug.”
Ephedrine (Ephedra)
• Amphetamine-like substance that acts as a
central nervous system and cardiovascular
stimulant
• Also known as ma huang
• Also sold as “herbal ecstasy” to alter
consciousness
Depressants
• Reduce the level of arousal, motor activity,
and awareness of environment
• Increase drowsiness and sedation
• Produce mild state of euphoria, reduction in
inhibitions, feeling of relaxation
• May impair mood, speech, and motor
coordination
Depressants
• Carry the potential for:
– Physical and psychological dependence
– Tolerance
– Withdrawal symptoms
• If two or more depressants are taken at the
same time, they produce an effect much
stronger than either drug produces when
taken alone (synergistic effect).
Sedative and Hypnotic Drugs
• By prescription only.
• Sedatives promote mental calmness and
reduce anxiety.
• Hypnotics promote sleep or drowsiness.
• Most common sedative-hypnotic drugs are
called benzodiazepines, popularly known as
tranquilizers.
Barbiturates
• Barbiturates are sedative-hypnotic drugs
that include barbituric acid and its
derivatives; these drugs include
amobarbital, pentobarbital, phenobarbital,
secobarbital, Tuinal, Rohypnol, and GHB.
Opiates
• Opiates are a group of chemically related drugs
derived from the opium poppy; depress the central
nervous system (CNS).
• Cause physical dependence, habituation, tolerance,
and serious withdrawal symptoms.
• Can be fatal because of respiratory failure.
• Morphine and heroin are derivatives of opium;
they block nerve transmission in the CNS,
suppressing mental and physiological functions.
Marijuana
• Forms:
– Hashish—sticky resin of the Cannabis sativa
plant
– Ganja—dried tops of female plants
– Bhang—contains smaller amounts of THC
– Sinsemilla—potent form of marijuana
• Active ingredient is THC.
• Low doses of THC produce:
– Euphoria
– Sense of relaxation
– Sometimes altered perception of time and space
Marijuana
• THC consumption can invoke:
–
–
–
–
Confusion
Anxiety
Hallucinations
Paranoia
• Research indicates that marijuana contains
carcinogens.
Marijuana
• Many states have legalized use for medical
purposes, such as:
–
–
–
–
–
Nausea caused by chemotherapy
Anorexia as a result of cancer
AIDS
Chronic pain
Migraines
Hallucinogens
• Derived from as many as 100 kinds of plants and
from chemical synthesis in the lab
• Alter perception, thought, mood, sensation, and
experience
• Most often ingested orally
• Produce tolerance but do not create physical
dependence or symptoms of withdrawal; there is a
danger of psychological dependence
Phencyclidine (PCP)
• PCP was originally used as an animal
anesthetic; it is no longer legal and is used
now only as an illegal recreational drug.
• The effects of PCP vary, depending on the
dose and route of administration; it can be:
– A stimulant
– A depressant
– A hallucinogen
Inhalants
• Depressants of the CNS
• Intended effect: Loss of inhibition
• Unintended effects:
– Dizziness
– Amnesia
– Inability to concentrate
– Confusion
– Impaired judgment
– Hallucinations
– Acute psychosis
Inhalants
• Chemical substances that vaporize rapidly and
when inhaled produce various kinds of depressant
effects similar to alcohol
• Model airplane glue, nail polish remover, paint
thinner, gasoline, aerosols, amyl nitrite, and
chloroform
• Do not produce tolerance or withdrawal, nor do
they induce physical dependence
• Can damage the kidneys, liver, and lungs
Anabolic Steroids
• Synthetic derivatives of the male hormone
testosterone.
• Taken orally or injected.
• Produce increased lean muscle mass, strength, and
ability to train longer and harder.
• Side effects include liver tumors, jaundice, fluid
retention, high blood pressure, severe acne, and
trembling.
Reducing Drug Use
• People are overmedicated and overly
dependent on drugs.
• The healthiest approach is to be as free of
drugs as possible.
• Wellness is not achieved by taking drugs.
• All drugs are dangerous, and illegal
recreational drugs are especially dangerous.