THE USE AND ABUSE OF DRUGS
1.3 Drugs
Summary of Specification content
Testing of new drugs and clinical trials.
Thalidomide
Learning Outcomes
Define the term ‘drug’.
Give examples of medical drugs.
Explain why drugs need to be tested before they
can be prescribed.
Describe the uses and problems associated with
thalidomide.
Explain how the drug testing procedure for
thalidomide was inappropriate.
Describe the main steps in testing a new drug.
Explain the terms placebo and double-blind trial.
Discuss:
what is a drug?
Names of medicines.
Medicines from plants
Drugs are chemicals
that affect the way cells work
That have an effect on the processes of the body
Medicinal drugs
Have a beneficial effect
Used for treating disease, injury and pain
Example: - Paracetemol
Effective painkiller
High doses can cause liver damage
In extreme cases it can be lethal
Recreational drugs
Some drugs are taken for pleasure
These include
Caffeine
Alcohol
Cannabis
Nicotine
Heroin
Natural medicines
Many of the chemicals used to make medicines
occur naturally in plants
aspirin
white willow bark
quinine
to treat malaria
from Cinchona tree
morphine and codeine
analgesics
from opium poppies
Natural medicines
75 – 80% of the world’s population use medicines
originally derived from plants
Many of these plants are found in rainforests
The rosy periwinkle is the source of two chemicals that are
used to treat cancer.
Obtaining drugs from plants
Many of the plants contain these chemicals to
protect them from herbivores
Problem
they are harmful to other living organisms
could be potentially harmful to humans if used in drug
preparations
So any potential drug has to be tested for:
efficacy
toxicity
Modern Drug Testing
Modern clinical trials are double blind trials, where
some patients are given a placebo.
Placebo
compound presented in the same way
Double blind
neither doctors nor patients know who gets drug or placebo
avoids bias in ‘looking for results’
Modern Drug testing
Stage 1: Laboratory
Phase 1 Clinical trial
Animals or tissues used
in a lab to find out
Low doses tested on a
group of healthy
people
Level of toxicity
Efficacy – does the drug
work?
Evaluate safety
Identify side effects
Modern Drug testing
Phase 2 Clinical trial
Phase 3 clinical trial
Larger group of people
Large groups of people
See if it is effective
Further evaluate safety
Determine optimum dose
Confirm effectiveness
Monitor side effects
History of drug testing
Digitalis
is a natural toxin found in
foxgloves
can be fatal in even
quite small doses.
used for centuries in
herbal remedies to treat
some heart conditions.
William Withering
rigorously tested
digitalis and brought it
into conventional
medicine in 1775.
Testing
a new
drug
Testing a new drug
Compare the two flow charts by answering the
following questions
What similarities are there?
What differences are there?
In what way is the current system of drug testing safer and
more reliable?
What do we gain nowadays from testing the drug on healthy
volunteers first?
Why is it important to randomly assign patients to the
treatments and have a double blind trial?
What similarities are there?
In both cases a potentially useful medicinal
substance was identified
First small and then larger groups of patients were
treated with the drug
What differences are there?
The current method seeks single active ingredients
Animal trials are used before testing on humans to
assess
efficacy
toxicity
Drug tried out on a group of healthy people first
confirms whether drug behaves in the body in the way
predicted by the lab tests
effects of different doses monitored
Independent review of data carried out in current
system
Further differences
Statistical analysis of data
to see if any difference is due to
chance
the drug
Once regarded as effective and safe drug has to be
strictly licensed before it can be marketed
In what way is the current system of drug
testing safer and more reliable?
Safer
Use of specific active ingredient should allow a more precise
dose to be given
Any serious ill effects may be detected in the animal trials first
More reliable
Uses larger samples reduces effects of chance
Double blind testing avoids patient/researcher bias in
observing, recording and interpreting effects
Statistical analysis of data improves accuracy of conclusions
as to whether or not drug has an effect
What do we gain nowadays from testing
the drug on healthy volunteers first?
Check no unexpected side effects
Observe behaviour of drug in a human e.g. is the
compound absorbed, how is it distributed, is it
metabolised and broken down too quickly, is it
excreted before it has an effect etc.
Why is it important to randomly assign patients to
the treatments and have a double blind trial?
Prevents
subconscious prediction or influence of the outcome by both
patient and researcher
psychosomatic influences
In the news
Sometimes things do go wrong!
http://news.bbc.co.uk/1/hi/england/london/4811626.stm
Ethical issues here!
http://www.bbc.co.uk/science/hottopics/animalexperiments/
http://www.beep.ac.uk/content/396.0.html
Even licensing can lead to controversy!
http://www.bbc.co.uk/stoke/content/articles/2005/09/26/her
ceptin_intro_2005_feature.shtml
Even licensing can lead to
controversy!
http://www.bbc.co.uk/stoke/content/articles/2005/0
9/26/herceptin_intro_2005_feature.shtml
Use of animals in research
http://www.mrc.ac.uk/NewsViewsAndEvents/News/
MRC003445
http://news.bbc.co.uk/1/hi/sci/tech/5365206.stm
Thalidomide
Thalidomide
drug used in the 1960’s as a sleeping pill
Effective at relieving morning sickness in pregnant women,
but had not been tested for this use
Reduced the development of blood capillaries in the foetus and
babies were born with underdeveloped arms and legs
Banned as soon as these side effects were noticed
Currently used for
Treating leprosy
Treating cancer
Thalidomide Activities
Use pictures to relate uses and problems associated
with thalidomide.
Research and produce a report on thalidomide –
original use, use in pregnant women, current uses.
How Science Works - ICT
You have developed a drug that can make people
more intelligent. Create a multimedia advertising
campaign explaining what your drug can do and
showing that it has been properly tested and is safe
to use.
PPQ Jan 10 (H) Question 4
(a)
testing for toxicity / see if it is safe / see if it is dangerous / to
see if it works
ignore side effects unqualified 1
(b)(i)
testing for side effects / testing for reactions (to drug)
ignore to see if it works
do not accept dosage
(b)(ii) any one from
dose too low to help patient
higher risk for patient
might conflict with patient’s treatment / patient on other
drug
effect might be masked by patient’s symptoms / side effects
clearer
ignore immune system
(c)
to find optimum dose
allow testing on larger sample or it makes results more reliable
allow to find out if drug is effective / find out if drug works on
ill people
(not just if drug works)
(d)(i)
(tablet / drug / injection) that does not contain drug
allow control / fake / false
allow tablet / injection that does not affect body
do not accept drug that does not affect body
(d)(ii)
neither patients nor doctors
Drug trialling – Suggested Activities
Discuss:
Discuss drug safety and how drugs are tested today.
Activity:
Cards/cut-outs to sequence stages in drug testing and
trialling and purpose of each stage.
Summary of Specification content
Statins lower the amount of cholesterol in the blood.
Recreational drugs
Learning Outcomes
Describe and evaluate the effect of statins in
cardiovascular disease.
Cholesterol Revision
Cholesterol
is produced naturally in the liver
Some people have high cholesterol levels
Too much cholesterol
increases the build up of fatty deposits in artery walls
Increases risk of heart disease
Evidence that reducing cholesterol in the blood reduces the
risk of heart disease and heart attacks
Statins
Statins
Reduce the production of cholesterol by the liver
Reduces blood cholesterol levels
Used to treat patients who are at risk because they have a
high cholesterol and a history of heart disease in their family.
Task: Interpret data on statins
any two from:
balance between two important for good heart health
ignore blood pressure
high LDL causes heart disease / high Cholesterol
do not accept converse argument
high HDL reduces heart disease / cholesterol
do not accept converse argument
heart attacks greater amongst patients with low HDL
levels
ignore statins cause heart disease
statins reduce heart attacks of patients or placebo is
less effective
ignore comparative effects of the two statins
allow pravastatin is more effective supported by
appropriate calculations
Revision – drug testing
T
toxicity
H
Healthy people for side effects
P
Patients for effectiveness
D
Patients for dose
Make your own mnemonic to remember the
sequence of events in drugs testing.
Learning Outcomes
Name some recreational drugs.
Describe some effects of caffeine on the body.
Recreational drugs
A drug is any chemical that alters how our body
works
Drugs that affect the central nervous system control
the movement of chemicals across the synapses.
Drugs have similar shapes to these chemicals and can mimic
what they do.
Recreational drugs are taken for pleasure
Recreational drugs
Legal
Alcohol
Caffeine
Nicotine
Illegal
Cannabis
Cocaine
Heroin
Ecstasy
All of these may have
adverse effects on the
heart and circulatory
system.
Drug Dependence
Chemical Dependence
Psychological dependence
the body adapts to the
presence of the drug.
When the chemical is
removed the body is no
longer able to function
normally.
The body then goes into
withdrawal symptoms
such as hallucinations,
fevers, nausea (feeling
sick) and shakes.
These are real, physical
signs.
the person feels a need
for the drug.
They feel unable to
cope without the drug.
For example:
some smokers need to
chew sweets after they
give up because they miss
having a cigarette in their
mouths.
Caffeine
A stimulant is a drug that increases the activity of the
nervous system.
It can raise the alertness, emotions or mood.
Caffeine is a mild stimulant found in tea and coffee.
Prolonged overuse may lead to problems with the
heart, stomach and pancreas.
Discuss: Brainstorm on recreational drugs, sort into
legal and illegal and discuss why people use them.
How Science Works: Investigate the effect of
caffeine on heart rate or reaction time
Summary of Specification content
Recreational drugs
Impact of legal drugs on health is greater than illegal
drugs as more people use them.
Learning Outcomes
Evaluate the impact of smoking on health.
Evaluate why some people use illegal drugs for
recreation.
Evaluate claims made about the effect of
prescribed and non-prescribed drugs on health.
Smoking
Benson And Hedges Gold 20 Pack
£7.25
Lambert And Butler King Size 20 Pack
£6.89
Decide how many cigarettes you are going to smoke in one day
Calculate how much you will spend on cigarettes in a week
Calculate how much you will spend on cigarettes in a year
If you started smoking at 16 and continued to smoke until you
were 65, how much money will you have spent on cigarettes?
Smoking and Health
To understand the effects of smoking you need to
look at the three components of cigarette smoke
Nicotine
Carbon monoxide
Tar
Nicotine
Nicotine is
Addictive
a stimulant
make the heart beat faster
Increasing the normal heart beat rate can cause stress for the
heart which can lead to heart disease.
Carbon Monoxide
This gas binds irreversibly to the haemoglobin in red
blood cells preventing them from carrying oxygen.
This will make the smoker more out of breath.
Smoking during pregnancy
Reduces the amount of oxygen which is being passed on to
the developing foetus
This slows down the growth of the foetus as it develops.
Tar
Tar is a mixture of many different chemicals.
It prevents the cilia in the lungs from working and so
the dirt and tar cannot be removed from the lungs.
The tar damages the delicate alveoli, often making
them burst.
This reduces the surface area of the lungs and leads
to breathing problems like Emphysema and COPD
(chronic obstructive pulmonary disease)
Carcinogens
Tar contains carcinogens which are chemicals which
can cause cancer.
A cancer is an abnormal growth of cells caused by a
change in the genes which control growth.
The tumour damages healthy cells and tissues as it
grows and can spread to other areas of the body.
Smoking increases the risk of lung cancer, mouth
cancer and throat cancer.
Pupil Activities
Poster to show effects of chemicals in smoke on the
body.
Show health warning on packets of cigarettes; video
clips of smoking adverts. Why do people smoke?
Further information
Useful information on drugs can be found at
www.talktofrank.com
A useful tool about smoking can be found on the
NHS website at www.nhs.uk by searching ‘smoking
calculator’.
Further information on smoking can be found at
www.ash.org.uk
Jun 09 Qu 3 BLY1H
(a)(i)
tobacco / nicotine / alcohol accept solvent / glue /
caffeine
ignore cigarettes / coffee
(a)(ii)
cannabis / heroin / cocaine allow eg crack / weed /
ecstasy / LSD / amphetamine / speed / steroids / GHB
(b)(i)
heroin / cocaine / tobacco / nicotine ignore alcohol /
cigarettes / cannabis / caffeine / coffee
(b)(ii)
alters body chemistry
ignore withdrawal symptoms / craving
ignore non-chemical effects on nervous system
Jun 09 Qu 3 BLY1H
(c)
any two from:
increase in cannabis smoking increases (%) depression
greater effect in women
allow women become more depressed
depression linked with / not directly caused by cannabis
not all cannabis smokers get depression
ignore cannabis causes depression
Jan 09 Qu 3 BLY1H
(a)(i)
does not contain drug / chemical
allow eg fake / sugar pill / dummy drug
(a)(ii)
as control or to see if the effects are psychological or allows
blind testing
allow ‘to compare (with NRT)’
(b)(i)
gum
allow gum placebo
allow placebo
(b)(ii)
high / highest number of participants / people or
correct number given ie gum 16706, gum placebo
9319, placebo 16458
(c)(i)
nasal spray
(c)(ii)
highest percentage of people stopped / 24%
stopped
biggest difference between treatment and placebo
allow ‘highest by 4%’ for 2 marks
Summary of Specification content
Recreational drugs
Impact of legal drugs on health is greater than illegal
drugs as more people use them.
Learning Outcomes
Evaluate the impact of alcohol on health.
Evaluate why some people use illegal drugs for
recreation.
Evaluate claims made about the effect of
prescribed and non-prescribed drugs on health.
Alcohol and Health
The alcohol in alcoholic drinks such as wines, beer
and spirits is ethanol.
It is a depressant
It slows down impulses in the nerves and brain.
Health
Small amounts of alcohol help people to relax
greater amounts lead to a lack of self-control.
Long-term effects of alcohol include damage to the liver and
brain.
Alcohol may also cause weight gain
it is addictive.
In an exam you may be asked to:Discuss effects of alcohol on the body,
Recommended units for men and women.
Calculate number of units of alcohol consumed.
Relate smoking and alcohol to NHS costs.
Summary of Specification content
Recreational drugs
Cannabis
Drug addiction and withdrawal symptoms – heroin
and cocaine.
Learning Outcomes
Describe the effects of cannabis on the body.
Consider the possible progression from recreational
to hard drugs.
Describe the effects of heroin/cocaine addiction
and withdrawal symptoms.
Cannabis
Cannabis is an illegal drug that can be smoked,
producing feelings of well-being.
like tobacco it can cause lung cancer and
bronchitis.
it can cause permanent damage to the mental
health of its users.
Research has shown that cannabis has some useful
painkilling properties, but it is illegal to prescribe it for
this use.
Card sort
Cut and sort into arguments for pro and antilegislation for cannabis
It can be used for nervous
conditions to relieve anxiety due
to its relaxing properties
Cannabis can be an effective
pain killer for diseases such as
cancer and multiple sclerosis
It would reduce crime as there
would be no need for a “black”
market for the drug
No-one has ever died from an
overdose of cannabis
Cannabis is addictive due to the
tobacco it is mixed with
Cannabis can be a starter for
harder more dangerous drugs
It will make the drug more readily
available to younger citizens
It can be the cause of many
mental conditions later in life
It is a stress reliever, which could
It slows down your reactions
save money for the NHS, and
making it almost impossible to
reduce the amount of people on
make informed decisions
sick pay.
As well as its own effects, it holds It contains carcinogens 6 times
all the bad effects of tobacco, stronger than those in tobacco,
when smoked with tobacco.
which can cause lung cancer.
Interpret data on cannabis use and progression to
hard drugs.
Does cannabis lead to hard drugs?
Cannabis can cause mental illness in some people
Cannabis is an illegal drug which is bought from
dealers
This brings cannabis users into contact with hard
drugs such as heroin
Not all cannabis users go on to hard drugs
Nearly all heroin users previously smoked cannabis.
Withdrawal
Once addicted people will suffer withdrawal
symptoms if they don’t take the drug.
Withdrawal symptoms can be
Psychological e.g. paranoia
Physical e.g. sweating and vomitting
Websites
Information on cannabis can be found on the NHS
website at www.nhs.uk by searching ‘the dangers of
cannabis’.
Further information on drugs can be found on the
following websites www.dare.uk.com
www.nida.nih.gov and on the NHS website at
www.nhs.uk by searching for ‘drugs’
Summary of Specification content
Steroids and performance enhancing drugs.
Learning Outcomes
Evaluate the use of drugs to enhance performance
in sport.
Consider the ethical issues of performance
enhancing drugs.
Describe some effects and risks of these drugs.
Drugs in sport
Some atheletes use drugs to enhance their
performance
Steroids are used to build up muscle mass, other
drugs can improve stamina
Strong painkillers are banned
Athlete might ignore an injury, suffering further damage
Performance enhancing drugs can damage the
body permanently
Drugs in Sport
Some athletes take illegal substances to enhance
their performance, an activity known as ‘doping’.
There are 5 'doping classes which are categories of
banned drugs:
Stimulants
Anabolic agents - steroids
Diuretics
Narcotic analgesics
Peptides and hormones
Drugs in sport
Doping class
Effect on performance
Dangerous side-effects
Stimulants
Make athletes more alert
and mask fatigue
Can cause heart failure,
addictive
Anabolic agents - steroids
Help athletes to train
harder and build muscle
Increased aggression
andkidney damage
Diuretics
Remove fluid from the
body. Used :to make the
weight, eg in boxing
to hide other drug use
Causes severe dehydration
Narcotic analgesics
Mask pain caused by injury
or fatigue which can make Addictive
the injury worse
Peptides and hormones
EPO (Erythropoietin) red
blood cells - gives more
energy
HGH (Human Growth
Hormone) - build muscle
EPO - risk of stroke or heart
problems.
HGH - abnormal growth,
heart disease, diabetes,
arthritis etc
Questions to think about
Is it unethical to take drugs to enhance
performance?
Are there any current news items regarding the use
of drugs in sport?
Lance Armstrong - cycling
Alan Baxter - Skiing
Research:
Research types of drugs used in sport and their
effects on the body and produce a table.
Activity:
Role play, write a story or debate about using drugs
in sport; random drug testing; getting caught
cheating.