All drugs affect the brain.

Different drugs (including alcohol and tobacco) act on different areas of the brain and alter its chemical balance. It’s these changes that cause the feelings and sensations people get when they take drugs.

The effect of drugs varies from substance to substance and it is not possible to say exactly how a particular drug will affect someone. Drugs can be more harmful for young people because their bodies and brains are still developing.

The same drug can also have very different effects at different times, depending on its purity (which can vary a lot) and the person’s mood, health, circumstances and surroundings.

Some drugs are more addictive than others and some people get addicted more easily. Some drugs can trigger underlying mental health problems and make existing ones worse.

Different types of drugs are grouped by their main effects and fall into three categories: stimulants, depressants and hallucinogens.

Some examples of these are:

Drug Group Drug Effects
Stimulants (uppers) Amphetamine
Cocaine
Increase energy, activity, heart rate, blood pressure
Depressants (downers) Alcohol
Heroin
Solvents
Slow down reactions, heart rate, breathing
Hallucinogens Cannabis
LSD
Magic Mushrooms
Cause hallucinations (see, hear and feel things differently).

While some argue that those who experiment with drugs might come to no long-term harm, some drugs like heroin are highly addictive and dangerous, and can occasionally cause very serious physical reactions, including drug overdose.

In the meantime, more and more new drugs are appearing, as well as new ways of taking older ones. Because they haven’t been around for long, less is known about how new drugs, and new ways of taking older ones, affect people. Some have turned out to be more dangerous than first thought.

It’s also very dangerous to take several drugs at once. Many people who have died from a drugs overdose did so because they had taken a combination of drugs, often combined with alcohol.

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