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Drug use and abuse

How often do you see drugs being used?


What are drugs?

A drug is any chemical substance that affects the physiological state of the body, such as how the central nervous system (CNS) works.

depressants – e.g. alcohol, solvents

stimulants – e.g. caffeine, cocaine

Drugs can be categorized according to whether they are legal or illegal, or by the type of effect they have on the body. For example:

painkillers – e.g. aspirin, heroin

hallucinogens – e.g. LSD

performance enhancers – e.g. anabolic steroids.


What do stimulants do?

Stimulants speed up the activity of the nervous system by increasing the release of neurotransmitters at certain synapses in the brain. This causes:

Common stimulants include caffeine, nicotine, cocaine and ecstasy.

improved memory and endurance

increased alertness

raised heart rate and blood pressure

reduced appetite.


What do depressants do?

Depressants slow down the activity of the nervous system by reducing the release of neurotransmitters at certain synapses in the brain.

Common depressants include alcohol, solvents and barbiturates.

This results in sleepiness and reduced anxiety, but high doses can lead to addiction.

Some depressants, such as heroin, also reduce pain.


Why take drugs?

Medicinal drugs (e.g. painkillers, antibiotics) are used to treat diseases or disorders. They are obtained either with a prescription or over-the-counter at a pharmacy.

Recreational drugs (e.g. alcohol, nicotine, ecstasy) are used for leisure purposes, because they cause changes in mood, behaviour or perception.


Which type of drug?


Illegal drugs have no quality control. It is impossible to know how strong the dose is, or which substances the drugs have been mixed (‘cut’) with. Some drugs may only be 1% pure.

Why do drugs need to be controlled?

Medicinal drugs can be equally dangerous. Doctors are careful to prescribe the right amount of medicine to prevent patients from overdosing.

How are prescription andover-the-counter drugs developed?


How are new drugs developed?


Drug trials

Few drugs successfully pass each stage of development. For every new drug launched, thousands are abandoned.

The drug must be tested in thousands of patients to see how effective and safe it is. Why are so many patients needed?

To minimize bias in drug trials, patients and doctors are not told who receives the study drug and who takes a placebo: an inactive substance that looks like the drug.

This is called a double-blind placebo-controlled trial. How does this help?


Thalidomide was a drug used in the 1950s and 1960s as a sleeping pill. However, pregnant women who were given the drug to prevent morning sickness gave birthto babies with limb deformities.

What was thalidomide?

Since then, drugs have had to be tested according to very strict guidelines.

The drug manufacturers had tested thalidomide in animals, but the tests on pregnant animals had not been completed.

How did this happen?

Thalidomide is now being tested for the treatment of diseases such as leprosy and some cancers.


What are controlled substances?

In Britain, illegal drugs are called controlled substances and are classified into three categories (A, B or C) under The Misuse of Drugs Act (1971).

It is a criminal offence to:

Class A drugs are considered the most harmful and/or addictive, and different penalties are given for possession and dealing.

possess a controlled substance unlawfully

possess a controlled substance with intent to supply

supply, or offer to supply, a controlled drug

allow your property to be used for drug taking.


How are illegal drugs classified?


Should cannabis be legalized?

Recent studies have shown that cannabis can reduce muscle spasms and tremors in multiple sclerosis sufferers and relieve nausea in chemotherapy patients.

However, cannabis is a mild hallucinogenic and prolonged use is linked to increased risk of developing schizophrenia.

Is cannabis any more dangerous than alcohol? Should it be legalized?

Health experts also warn that smoking cannabis can lead to the use of ‘harder’ drugs.


What are gateway drugs?

A gateway drug is a substance that leads to experimentation with ‘harder’ and more addictive drugs.

Tobacco, alcohol and cannabis are often referred to as gateway drugs.

Some scientists think that taking a gateway drug could cause physiological changes in the brain that make the user more likely to use other drugs, but there is little evidence of this.

Others argue that users progress to harder drugs simply because they have access to them through drug dealers.

Why do gateway drugs have this effect?


What is addiction?

A person is said to be addicted to, or dependent on, a drug when they feel unable to stop taking it. There are two types of addiction:

psychological addiction –the person is compelled to take the drug to experience the effect it produces, rather than to treat withdrawal symptoms.

physiological addiction –the person is compelled to take the drug to avoid or reduce unpleasant or dangerous withdrawal symptoms.


How is addiction treated?

Different addictions are treated in different ways.

Psychological addiction is often treated using counselling.

Physiological addiction is initially treated using detoxification. In some cases, substitute drugs may be prescribed to reduce drug cravings.

What about addicts who don’t want to quit?

For example, methadone is offered to heroin addicts. Methadone is taken orally so it also reduces the risk of infections transmitted through sharing needles, such as HIV and hepatitis.


Tackling problems caused by addiction

Some people are lobbying the Government to legalize (or decriminalize) drugs.

These people argue that by making certain drugs available from specialist pharmacists or via prescription, drug-related crime could be halved.

Addicts could also have access to special drug injecting rooms (‘shooting galleries’) to get clean needles and use drugs in a safe environment.


Changing the law


What is alcohol?

Alcohol is a family of related substances, but most commonly refers to ethanol – the active ingredient in alcoholic drinks.

Alcohol is quickly absorbed into the bloodstream, where it starts to have an effect on the CNS.

The effects of alcohol vary from person to person and with factors such as: rate of consumption level of food/water intake

body weight/body fat.

age and gender


The short-term effects of alcohol

Alcohol also makes blood vessels dilate, leading to heat loss.

Small amounts of alcohol cause a person to feel relaxed and less inhibited. It can therefore appear to stimulate people.

However, further consumption has a depressant effect, making reactions uncoordinated and impairing speech.

Alcohol is a diuretic, which means it causes more urine to be produced than normal. This can lead to dehydration, which contributes to a hangover!


Does it matter how much you drink?

Why does alcohol increase the risk of accident or injury?

Alcohol slows down reaction times, gives a false sense of confidence and affects a person’s decision-making ability.

About 40% of admissions to hospital A&E wards are related to alcohol consumption, rising to 70% between midnight and 5am at weekends.

At high levels, alcohol causes vomiting, unconsciousness and can even cause breathing to stop and lead to death.


How much is it safe to drink?

The UK Department of Health advises that men should drink no more than 4 units of alcohol per day, and women no more than 3 units.

How much is 1 unit of alcohol?

3

2

2

2

1.5

1

1 pint of strong lager

1 pint of bitter

1 pint of cider

1 alcopop

175 mls of wine

35 mls of spirit

Drink Units of alcohol


Effects of alcohol by dose


Like all drugs, alcohol is broken down, or metabolized, by the liver.

The long-term effects of alcohol

Heavy drinkers are also at increased risk of cancer and damage to the brain, kidney and immune system.

Over time, heavy drinking damages liver cells, causing them to produce fibrous scar tissue which blocks liver function. This is a disease called cirrhosis.


What is tobacco?

When tobacco smoke is inhaled, the nicotine quickly enters the bloodstream and has a stimulating effect on the nervous system.

Tobacco is made from the leaves of the tobacco plant, which contain small amounts of nicotine. Cigarettes are made from finely cut and dried tobacco leaves.

At high concentrations nicotine is poisonous and is used as insecticide!


The dangers of smoking


Smoking kills

Smoking is associated with over 20 fatal diseases and 50 long-term debilitating illnesses. Half of all smokers will die prematurely.

What are the most common causes of death in smokers?

How does smoking damage health?

lung cancer

bronchitis/emphysema

coronary heart disease.


Spot the difference

Which set of lungs would you prefer to have?


Smoking patterns and lung cancer


The chemicals in cigarette smoke


Nicotine

Nicotine is addictive because it increases levels of the neurotransmitter dopamine in the brain. This produces feelings of enjoyment and motivation.

Many smokers find it difficult to quit smoking because of the symptoms of nicotine withdrawal, which include:

What type of products are available to help smokers quit?

headaches

anxiety and sleeplessness

weight gain.


The effect of smoking on oxygen supply

oxygen

carbon monoxide

carbon dioxide

Red blood cells are normally saturated with oxygen when they leave the lungs.

Carbon monoxide in cigarette smoke prevents red cells from picking up oxygen.

alveolus in the lung

capillary

red blood cells


Smoker’s cough


Smoking during pregnancy is risky for both mother and baby.

Pregnancy and smoking

Babies exposed to smoke during gestation are at increased risk of:

Pregnant women who smoke are at increased risk of: miscarriage foetal death detachment of the placenta premature labour.

limb deformities low birth weight.

sudden infant death syndrome


Why do people smoke?

There are many reasons why people say they smoke:

What is your response to each of these reasons?

“It calms my nerves”

“It keeps weight down”“It looks good”

“I haven’t got the will power to quit”

“I smoke low tar cigarettes – they’re safer”


alcohol – A depressant that is widely used recreationally and can cause liver and brain damage.

addiction – Physiological or psychological dependence on a drug.

carcinogen – A substance that increases the risk of developing cancer.

cirrhosis – Liver disease caused by long-term alcohol abuse.

depressant – A drug that reduces synaptic transmission.

drug – Any substance that changes the body’s chemistry.

Glossary (1/2)


hallucinogen – A drug that distorts perceptions.

nicotine – The addictive drug in tobacco.

prescription drug – A substance only legally available from a healthcare professional.

recreational drug – A drug used for non-medical purposes.

stimulant – A drug that increases synaptic transmission.

tar – The sticky substance found in cigarette smoke.

withdrawal symptoms – Unpleasant physical effects that appear when use of an addictive drug ceases.

Glossary (2/2)


Anagrams


Physiological effects of alcohol


Effect of cigarette smoke chemicals


Multiple-choice quiz

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