What are the main effects of drugs?

What are the main effects of drugs?
Drugs can be broadly divided into three categories based on their main effects.
They may act solely as stimulants, depressants or hallucinogens. Quite a few drugs show two of these effects at the same time, and are then described either as stimulant hallucinogens (e.g. ecstasy) or as depressant hallucinogens (e.g. cannabis).

Stimulants make you feel like you have lots of energy and confidence. They include cocaine, speed, ecstasy, and mephedrone.

Depressants make you feel relaxed and chilled out. They include alcohol, tranquillisers, heroin and cannabis.

Hallucinogens can make you view reality in distorted way and sometimes cause vivid hallucinations. They include LSD and magic mushrooms.

In addition to these 3 broad categories, each particular drug has its own specific effects and risks.

When you obtain drugs anywhere other than from a reliable pharmacy, it can be difficult to say exactly what effects and risks the drug may have. A drug may be quite new and its harms may not yet be fully known, or the drug you are actually taking may not be what you believe it to be (e.g. both PMA and mephedrone have been sold as MDMA/ecstasy). Information on the known effects of each drug is available in the A-Z of drugs on the FRANK website.

How long will a drug stay in my system?
This depends on which drug you are talking about and what method is being used to test for the drug. The list below shows the drug detection times (using a urine test) for the most common drugs:

  • Alcohol 12 - 24 hours
  • Amphetamine 2 - 3 days
  • Cannabis 2 – 7 days – 1 month (for regular users)
  • Cocaine 12 hours – 3 days
  • Crystal Meth 2 - 3 days
  • Diazepam 1 - 2 days
  • Ecstasy 2 - 4 days
  • GHB up to 24 hours
  • Heroin 1 - 2 days
  • Ketamine 5 - 7 days
  • LSD 2 - 3 days
  • Magic Mushrooms (Psilocybin) up to 8 hours
  • Methadone 2 days
  • Steroids 14 days (oral) - 1 month (injected)
  • Temazepam 1 - 2 days (longer after injecting)

With so much information about drugs out there, we recommend talking to FRANK. FRANK gives the lowdown on legal and illegal drugs. It tells you about their effects, risks, what goes into them and lots of other information. Like what to do if you’re worried about a mate. Or how to tell if a friend is suffering from crystal meth addiction or other types of drug addiction. Or what happens when you mix drugs.
There are also stories from people who’ve been there, done that. And details on where to go for help and advice so that you feel more confident about drugs.

For more information about drugs or to find support near you, visit the FRANK website:


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