Download IB chemistry SL revision Option D

IB chemistry SL revision
Option D
1. Pharmaceutical products
What are the effects of
medicines and drugs on the
functioning of the body?
What are the stages involved
in the research, development
and testing of new
pharmaceutical products?
 alter the physiological state, including consciousness, activity level or
coordination
 alters incoming sensory sensations
 alter mood or emotions
1. Identify disease, a ‘target’ molecule
2. Identify target e.g. gene or enzyme which is necessary for disease to
progress.
3. Identify ‘lead’ molecule that can act on gene/enzyme in the disease
organism or host and isolate or manufacture it.
4. Preclinical trials: ‘in vitro’ and ‘in vivo’:
5. Clinical trials : on people/placebo effect
What are the different
methods of administering
drugs?
What is the therapeutic
window of a drug?
What does tolerance mean?
What are side-effects of a
drug?
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6. Submission of reports on the drug and its trials to international or
national regulatory bodies.
7. Monitoring of the drug after it has been launched; molecule might
need further structural changes.
 Oral: taken in by the mouth e.g. tablets, syrups, capsules.
 Parenteral - by injection:
o intravenous: into a vein of the blood stream – used for
immediate impacts as its fastest method; drug is
immediately pumped around the body by the blood.
o intramuscular i.e. into the muscles, e.g. many vaccines,
local anaesthetics, usually used when a large dose needs
to be administered.
o subcutaneous: in the layer of the skin directly below the
cutis (dermis and epidermis) e.g. dental injections,
morphine, insulin. Slow.
 Inhalation: e.g. medication for respiratory conditions such as asthma.
 Rectal: inserted into the rectum e.g. treatment for digestive illnesses,
drug absorbed into the blood stream.
 Skin patches: e.g. hormone treatments.
The therapeutic window is the range in concentration over which a drug
can be safely administered to a typical population.
 The lowest level of concentration is the called the effective level
(therapeutic level) or ED50; below this level the drug loses its
therapeutic effect
 The highest level is the toxic or LD50 level (= the dose needed to kill 50
% of (animal) population) above which adverse side-effects can occur
Tolerance refers to the body’s reduced response to a drug i.e. its
therapeutic effect is less than what it is intended, usually as a result of
taking the drug over a long period of time. As a result more of the drug
needs to be taken to achieve the same initial physiological effect
Side-effects are physiological effects which are not intended and
therefore undesired (intended =
therapeutic effects)
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2. Antacids
How can excess acidity in the
stomach be reduced by the
use of different bases?
Why are alginates added to
antacids?
Why is an anti-foaming agent
added to antacids that have
carbonate in them?
By adding antacids such as aluminium hydroxide, magnesium
hydroxide and sodium hydrogencarbonate. These chemicals can
neutralize the acid as they have OH- or HCO3- ions which can react
with H+ from acid to form water and salt.
Alginates produce a neutralizing layer on top of stomach contents
and this prevents acid in the stomach from rising into the
oesophagus and causing heartburn.
Anti- foaming agents such as dimethicone reduce the bloating of the
stomach as a result of the carbon dioxide production.
3. Analgesics
How do mild analgesics
prevent pain?
by interfering with the production of substances, such as
prostaglandins, that are produced by injured tissues and that cause
pain, swelling or fever.
How do strong analgesics
prevent pain?
by temporarily bonding to receptor sites to pain impulses in the brain
or other parts of the central nervous system such as the spinal cord.
This prevents the transmission of pain impulses i.e. blocking the
signal without depressing the central nervous system.
Name examples of mild
analgesics.
Name sxamples of strong
analgesics.
What are the advantages of
using aspirin?
aspirin, paracetamol
codeine, morphine, heroine
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What are disadvantages of
using aspirin?
What are the advantages of
using paracetamol?
What are disadvantages of
using paracetamol?
What do the structures of
morphine, codeine and
heroine have in common?
How are the structures of
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reduces fever more effectively – antipyretic (=drug which reduces
fever)
also useful in preventing the recurrence of heart attacks and
strokes and also thins the blood (beneficial side-effects) and
reduces blood clotting
also anti-inflammatory – reduces inflammation or swelling
ulceration
stomach bleeding due to its acidic properties
allergic reactions
Reye’s syndrome in children (a potentially fatal liver and brain
disorder) so not suitable for children
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reduces fever - antipyretic
very safe in the correct dose as it does not upset the stomach or
cause bleeding
 suitable for children
 can, in rare cases, cause blood disorders and kidney damage.
 easier to overdose and overdosage can lead to serious liver
damage, brain damage and even death.
 not a good anti-inflammatory
All three have the aromatic benzene ring, a tertiary amine, a double
bond and an ether group.
Both morphine and codeine also have a hydroxyl group. Heroine
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morphine, codeine and
heroine different?
What are the advantages of
using morphine and its
derivatives?
has 2 ester groups.
What are the disadvantages
of using morphine and its
derivatives?
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strong analgesics and therefore can relieve extreme pain
wide therapeutic window
relieves anxiety
induces relaxation
can be administered intravenously which results in faster
distribution of drug
euphoria, lack of self-control even dangerous behaviour
kidney failure.
addiction or physical dependence which leads to withdrawal
symptoms when drug is not taken e.g. restlessness, sweating,
fever, cramping, …
tolerance can become an issue with this type of drug as more of
the drug needs to be taken to achieve the same effect; in order to
achieve the desired effect heroin users may take doses which
exceed the lethal dose
Social:
o heroin users are more likely to commit crimes to pay for
gradually increasing doses of the drug
o diversion of energy and money; loss of job
o when administered intravenously can lead to transmission
of dangerous infections e.g. AIDS.
4. Depressants
What are effects of a low
dose of depressant?
What are effects of a
moderate dose of
depressant?
What are effects of a high
dose of depressant?
What are effects of a very
high of depressant?
What are the social effects of
alcohol use and abuse?
What are the short term
physiological effects of
alcohol use/abuse?
What are the long term
physiological effects of
alcohol use/abuse?
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may have little or no effect.
may induce sedation, soothing, reduction of anxiety, impaired
judgement
may induce sleep, unconsciousness, slurred speech, altered
perception
may cause organ failure, coma or death
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increased risk when driving or operating machinery
involvement in violence or crime
relationship problems
taking time off work as a result of sickness or death associated
with alcohol abuse
loss of income
hospital costs
lower economical production
reduces tension, anxiety and inhibitions
impairs function of central nervous system
dehydration
high dose can cause vomiting, unconsciousness
liver damage/cancer
cirrhosis – liver disease
increased blood pressure
heart disease or stroke
miscarriage and fetal abnormalities
tolerance and physical dependence
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What is the synergetic effect
of using alcohol with other
drugs?
the effect of the other drugs is often enhanced in the presence of
alcohol which can be dangerous e.g. with aspirin it can increase
damage to stomach and cause bleeding. In the case of sleeping
tablets and other sedatives it can cause coma or death.
How is potassium dichromate
used to detect alcohol?
Used in a breathalyzer; in a positive result (i.e. presence of alcohol in
the breath) the potassium dichromate changes form orange to green
when ethanol is present as the potassium dichromate is reduced and
the ethanol oxidized to ethanoic acid.
Infrared radiation is passed through breath, blood or urine sample.
The C–H bond in ethanol causes radiation to be absorbed at a
specific wavenumber which is 2950 cm-1. The intoximeter measures
the amount of absorption which depends upon the amount of ethanol
in the breath i.e. the more ethanol there is present the more IR is
absorbed. The amount or peak is compared against a standard (e.g.
allowed amount)
How does an intoximeter
detect alcohol?
How does chromatography
help to detect alcohol?
What are other common
depressants?
Describe the structure of
Prozac.
Describe the structure of
Valium.
Describe the structure of
Mogadon
Ethanol is separated from the blood or urine using gas-liquid
chromatography; area under ethanol peak on chromatogram
indicated amount of ethanol in blood or urine
prozac, valium, mogadon
aromatic benzene, ether, fluorine, amine, chloride ion
amide, aromatic benzene secondary amine, chlorine,
amide,aromatic benzene, secondary amine, NO2
5. Stimulants
What are the short term
physiological effects of
stimulants?
What are the long term
physiological effects of
stimulants?
What are amphetamines?
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increased heart rate, blood pressure, breathing rate
dilation of pupils
constriction of arteries
sweating
increased alertness and concentration
decreased appetite
 stimulating effects.
 increased risk of heart disease
 increased blood pressure
 coronary thrombosis
 stomach ulcers.
 tolerance: which leads to increased use as increased amounts
needed to produce same effect; increasing amounts cause
damage/death/overdose/lethal dose
amphetamines mimic the effects of epinephrine or adrenaline which
stimulates the sympathetic nervous system and they are therefore
known as sympathomimetic drugs.
an aromatic benzene ring and an alkyl chain
What do amphetamines and
epinephrine have in common?
What are amphetamines and
amphetamines have a primary amine whilst epinephrine has 3
epinephrine different?
hydroxyl groups and a secondary amine
What are the short term
 increased heart rate
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effects of nicotine?
What are the long term effects
of nicotine?
What are the effects of
caffeine?
Compare the structure of
caffeine and nicotine.
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increased blood pressure
reduced urine output
 increased concentration
 increased risk of cancer or stroke
 heart disease / thrombosis
 stomach ulcers
 emphysema
 bronchitis
 shortage of breath
 coughing
 bad breath
 yellowing of teeth or fingers
 adverse effect on pregnancy
 addiction to tobacco
 reduction in capacity of blood to carry oxygen;
 withdrawal symptoms / weight gain (on quitting);
caffeine is a stimulant. When consumed in large amounts it can
cause anxiety, irritability and sleeplessness. It is a weak diuretic
both have aromatic benzene and tertiary amine group; in fact
caffeine has three tertiary amine groups.
Caffeine also has two carbonyl groups.
6. Antibacterials
What contribution did
Alexander Fleming make to
the development of penicillin?
What contribution did Florey
and Chain make to the
development of penicillin?
How does penicillin work?
What are the advantages of
modifying the side-chain of
penicilins?
What is patient compliance?
Why is important patient
compliance important?
What are the effects of
overprescription of penicillins
or antibacterials?
discovered that penicillin inhibited growth or killed bacteria
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overcame the problems associated with isolating and
concentrating penicillin as Penicillin G
 showed that penicillin is harmless and effective on mice;
 first to use penicillin on a human;
 grew penicillin in large amounts;
Penicillins work by interfering with the chemicals that a bacteria
needs to form a cell wall. This prevents the formation of cross-links
within the cell wall. As a result the bacterial cell absorbs too much
water and bursts as the result of increased osmotic pressure.
 resistant to penicillinase enzyme which is an enzyme which can
break down penicillin G and which is found in some bacteria;
stops bacteria from destroying penicillin and becoming resistant
to them
 resistance to breakdown by stomach acid (so can be taken
orally).
Patients taking antibacterials as prescribed i.e. take all tablets and in
the correct dose.
If patients not being compliant allows bacteria to become resistant.
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leads to resistance by the bacteria to penicillin which makes
penicillin less effective; bacteria produced penicillinase, an
enzyme which destroys penicillin
resistant bacteria reproduce and pass on their resistance to
succeeding generations
useful bacteria may be killed
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7. Antivirals
How are viruses different from
bacteria?
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What are the different ways in
which antivirals work?
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What difficulties are associated
with solving the AIDS
problem?
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viruses are not self-reproducing as they need a host cell to
multiply; viruses insert DNA into host cells
viruses lack any metabolic functions so they do not grow, feed
or excrete
viruses consist only of genetic material and protective coating
viruses are smaller than bacteria
viruses mutate/multiply (much) faster than bacteria
altering the host cell’s genetic material so that the virus cannot
use it to multiply
preventing the viruses from multiplying by blocking enzyme
activity within the host cell.
preventing viruses from entering host cell and binding to cellular
receptors targeted by the viruses
preventing the release of viruses from the cell
HIV viruses can mutate rapidly
HIV viruses have similar metabolism to the metabolism of the
host cell so any drug could also damage host cell
high price of antiretroviral drugs
socioeconomic
cultural issues;
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