What are drugs?

Drugs affect the way your body and mind function; they can change how you feel, think and behave. People take drugs for different reasons and in different ways. Find out about legal and illegal drugs.

Drugs affect your mind and body

Drugs are substances 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. This makes them unpredictable and dangerous, especially for young people.

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

Why do people use drugs?

Drugs change the way your body or brain works. 

People 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 have a drug dependency and need to keep taking them to avoid withdrawal symptoms.

How are drugs made?

Drugs come from different sources:

  • plants – for example, cannabis, mushrooms, or tobacco
  • processed plant products – for example, alcohol, or heroin
  • synthetic chemicals – for example, ecstasy 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 makers often add impurities to make them go further. You cannot be sure what you are taking.

How do people take drugs?

People take drugs in different ways. Common methods include:

  • swallowing tablets or drinking liquids – the body absorbs the drug through the stomach lining
  • breathing them into the lungs – the body absorbs the drug through the lining of the lungs
  • snorting into the nose – the body absorbs the drug through the thin nasal lining
  • injecting – the user injects the drug directly into the bloodstream
  • through the skin – the body slowly absorbs the drug from a cream or patch
  • rectally or vaginally as a suppository – the body absorbs the drug through the bowel or vaginal lining.

No matter which way you take a drug, it will end up in your bloodstream and affect different parts of your body.

Legal and illegal drugs

Drugs can be:

  • legal – for example, alcohol, caffeine, and tobacco
  • illegal – for example, cocaine or heroin.

Legal drugs

Some drugs – such as alcohol, caffeine, and nicotine – are legal but may be subject to restrictions based on age, location of use, driving and point of sale regulations.

We regulate and control the active ingredients in legal drugs:

  • the alcohol content of drinks
  • the milligrams of nicotine in cigarettes.

Illegal drugs

Other drugs such as cannabis, amphetamines, ecstasy, cocaine and heroin, are illegal. They are not subject to quality or price controls and the amount of active ingredient varies. A person using illegal drugs can never be sure of how strong the drug is, or what is actually in it.

Different batches of an illegally manufactured drug may have different amounts of the drug and other unidentified additives.

It is against the law to possess, use, make, import or sell illegal drugs. The penalties for drug offences vary depending on the age of the offender (adult or minor), type of drug, quantities involved, previous offences, and the state or territory in which the offence happened.

Find out more about our drug laws.

Illicit drugs

Illicit drugs include:

  • illegal drugs
  • prescription medicines 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.

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