Mental health effects of street drugs and alcohol

Explains the mental health effects of street drugs, what might happen if you use street drugs and also have a mental health problem, and suggestions for where you might find support.

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Posted on 07/10/2013

About street drugs

This information is for anyone who wants to know about the effects of street drugs on mental health, including anyone who takes them or has dual diagnosis. It explains how taking street drugs can affect your mental health, and how different types of street drugs can affect your mental health in different ways. It explains different options for help and treatment, and includes information for family and friends.

What are street drugs?

Street drugs are substances people take to give themselves a pleasurable experience, or to help them feel better if they are having a bad time, or simply because their friends are using them. They include heroin, cocaine, cannabis, alcohol and some prescribed medicines.

Street drugs may be:

  • legal – such as caffeine, nicotine and alcohol.
  • illegal – this means it is against the law to have them or supply them to other people. Most street drugs are illegal.
  • controlled – these are drugs used in medicine, such as benzodiazepines. It is legal to take controlled drugs if a doctor has given you a prescription for them, but it is illegal to have them if not. It is also illegal to give or sell them to anyone else.

The way street drugs are legally classified does not reflect how harmful they are to your mental health. Illegal, controlled and legal drugs can all have a negative impact on you, whatever class (A, B or C) they are given.


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