Drugs affect your mind and body

Drugs are substances, other than food or water, that change a person’s mental or physical state. They can affect the way your brain works, how you feel and behave, your understanding and your senses.

Drugs can be both helpful and harmful and there are many different types of drugs.

Why do people use drugs?

Because drugs change the way your body or brain works they are used to prevent, treat or cure medical conditions such as illness or injury.

Some of these drugs are available through pharmacies, either over the counter or prescribed by a doctor. Others are illegal because they have harmful effects and can even cause death. Learn about the effects of taking drugs.

People also take drugs because:

  • they are curious and want to see what happens
  • they want to fit in or feel pressured by their peers
  • they enjoy the effect on their body — for example, feeling excited and energetic, or relaxed and calm
  • they help them cope with situations — for example, reducing pain or relieving stress
  • they’ve become addicted and need to keep taking them to avoid withdrawal symptoms

How are drugs made?

Drugs come from different sources:

  • plants that are grown — for example, cannabis, mushrooms, or tobacco
  • plant products that are refined in laboratories — for example alcohol, aspirin, or heroin
  • synthetic chemicals — for example, ecstasy, paracetamol or amphetamines

The processes used to make drugs varies widely, but drug products have 2 main types of ingredients:

  • active ingredients — the ingredients that biologically affect your body
  • inactive ingredients — these generally have no biological effect. They include binding agents, capsules, dyes, preservatives, flavourings and other ingredients

Legally manufactured drugs usually list all their ingredients, so you know what you are taking. Street drugs can contain almost anything as impurities are often added to make them go further. You cannot be sure what you are taking.

How are drugs taken?

A drug can be taken into the body in different ways, including:

  • swallowing tablets or drinking liquids — the drug is absorbed through the stomach lining into the bloodstream
  • breathing them in — the drug is absorbed through the lining of the lungs into the bloodstream
  • snorting — the drug is absorbed through the thin nasal lining into the bloodstream
  • injecting — the drug is injected directly into the bloodstream
  • through the skin — the drug is slowly absorbed from a cream or patch
  • rectally or vaginally as a suppository — the drug is absorbed through the bowel or vaginal lining into the bloodstream

The effects of drugs are different for each person and drug. Learn more about the effects of drugs and the different types of drugs.

Legal and illegal drugs

Drugs can be:

  • legal — for example, alcohol, aspirin, or tobacco
  • illegal — for example, cocaine or heroin

Legal drugs

Legal drugs are used for medicinal purposes — to prevent, treat or cure medical conditions such as illness or injury.

They can be bought:

  • without a prescription at supermarkets, health food stores or pharmacies — for example, over-the-counter drugs like paracetamol or cough medicine
  • with a prescription from a doctor at pharmacies — for example, blood pressure medications, strong painkillers or other medicines

Illegal drugs

Illegal drugs are forbidden by law — they affect people in different ways and are usually harmful, even causing death.

Find out more about Australia’s drug laws.

Illicit drugs

Illicit drugs include:

  • illegal drugs being used recreationally
  • prescription drugs that have been obtained illegally or are not being used for medicinal purposes
  • other substances that are being used inappropriately — for example, sniffing glue or inhaling paint thinner

Find more information about drugs on our Drug Help website.



Last updated: 
5 April 2019