What are drugs?

By  ReachOut     |    Updated: 21st April, 2017    |    4 min read

A drug is anything that changes how your brain works. People take them for all sorts of reasons. There are different types of drugs, with different effects. There are added dangers to taking illegal drugs. You also shouldn’t mix drugs. If you need to get help about drug use or you want to find more information, there are a number of places you can go.

What are drugs and why do people take them?

A drug is any chemical substance that you put in or on your body that changes how your body or brain works. Drugs are often taken for medical or recreational reasons. Drugs taken for medical reasons can be prescribed by a doctor or accessed over the counter at supermarkets or pharmacies. People aged 18 and over can legally purchase some recreational drugs, e.g. alcohol and tobacco, but other drugs, such as marijuana, ecstasy, cocaine, LSD and amphetamines are illegal.
People take different types of recreational drugs for many different reasons – to relax, to help them focus, as part of socialising, because they’re addicted, to fit in, because they’re bored or curious, or to escape their problems.

Types of drugs

There are three main types of drugs – depressants, stimulants and hallucinogens.

Depressants slow down messages to and from your brain. Alcohol, opiates (like heroin and morphine), cannabis, sedatives (like valium), and some glues, petrols and other solvents are all depressants. If you take different types of depressants at the same time you’re more likely to overdose (OD), so if you’re using depressant drugs, the safest way to do so is to stick to one type of drug. Large amounts of depressants can:

  • Make you pass out
  • Stop breathing
  • Make you feel sick and vomit

Stimulants speed up the messages going to and from your brain. Caffeine, nicotine, amphetamines (like speed or ice), ecstasy and cocaine are stimulants. Using stimulants:

  • Puts a strain on your heart
  • Increases your body temperature
  • Stops you feeling hungry
  • Can make you paranoid, anxious or psychotic

Mixing stimulants with each other or with depressants puts extra strain on your heart and can cause major health problems.


Hallucinogens change your perception of reality. LSD, magic mushrooms, ecstasy, mescaline, and high doses of cannabis are all hallucinogenic drugs. People who take hallucinogens often have ‘trips’ which is when they hear and see things that aren’t really there. How your ‘trip’ goes depends on your mood, state of mind and setting. You can’t predict whether it will be good or bad, or how strong it will be. Hallucinogens can:

  • Make you panicked, anxious or paranoid
  • Make you take risks you wouldn’t normally take
  • Make you lose touch with reality (psychosis)

Mixing drugs can be dangerous – and that includes alcohol. It can be dangerous because it can really mess up the chemistry in your body, and cause serious or life threatening damage to your health. It can also be dangerous because it could make you do dangerous things.

Illegal drugs

Drugs are made illegal when they pose serious risk to people’s health. Taking illegal drugs can be dangerous because, apart from the negative health impacts of the drug itself, there is no quality control over what you’re taking. You’ve got no way of knowing how strong or weak the drug is, or whether there are other dangerous substances mixed into it which could cause serious health issues. It’s possible that you might take way too much, or even different stuff to what you were after. If you get caught with illegal drugs by the police you can be arrested and charged.

Getting help with drugs

Drug use can impact on your physical and mental health, and you can also become addicted, but there are places where you can get help with dealing with drug-related issues. If you think you could use some help, you should visit your GP or another health professional.

Also check the related topics:  

Alcohol Cannabis Inhalents Ecstasy, ICE and other Amphetamines Benzodiazepines Smoking Grog and Other Drugs

Factsheet provided by ReachOut


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