The effects

What hallucinogens do to you depends on:

  • How much you take.
  • Your height and weight.
  • Your general health.
  • Your mood.
  • Your past experience with hallucinogens.
  • Whether you use hallucinogens on their own or with other drugs.
  • Whether you use alone or with others at home or at a party, etc.


The effects of hallucinogens are not easy to predict. The effects are different for different people and at different times.

The main effects of hallucinogens are changes in the way you perceive things with your senses. They can include strange sensations such as floating or your body becoming part of another object. Some people find these sensations interesting and pleasant, while others find the same effects unpleasant and disturbing.

Short term effects:

The effects can begin within half an hour of taking the drug and are strongest three to five hours after ingestion and last for up to 12 hours.

They can include:

  • Seeing, touching or smelling things in a distorted way or that don’t exist.
  • Intense sensory experiences (eg. Colours become very bright and sounds become sharper)
  • Mixing of the senses (eg you hear colours or see smells)
  • Changed sense of time (eg. Minutes can seem as hours or you can re-live something that happened a long time ago.)
  • Space becomes distorted
  • Strange bodily sensations.
  • Changed and intense thoughts
  • Emotional swings.

Effects on your body may include:

  • Your muscles twitch
  • You feel weak
  • You feel numb
  • Your pupils enlarge
  • You shake
  • You feel sick or vomit
  • Your heart beats faster
  • Your blood pressure rises
  • You breathe faster and deeper than normal
  • Your coordination is poor

Sometimes the effects of hallucinogens are negative. This is known as a bad trip and it is common among first time users. Effects can include:

  • Extreme anxiety or fear
  • Frightening hallucinations (eg spiders crawling on the skin)
  • Panic, leading to taking risks
  • Feelings of losing control or going mad
  • Paranoia
  • Suicide or violence.

If someone is having a bad trip they need to be reassured and comforted until the effects of the drug begin to wear off. This can take many hours and may not disappear altogether for several days.

Long term effects:

There a few known long-term effects of hallucinogens. However, flashbacks can happen days, weeks or even years after taking the drug. They can happen without warning, last for a minute or two and can be disturbing.

These flashbacks can be triggered by using other drugs, stress, tiredness or physical exercise. Regular users are far more likely to have flashbacks.

Some other long term effects may be damaged memory and concentration and may increase the risk of mental problems in some people.

It is important to remember that being intoxicated on any drug or drugs can affect your decision making and can decrease the ability to consent to sex. This can lead to risky sexual behavior such as unprotected sex which may result in you contracting a sexually transmitted diseases such as HIV, Hepatitis or Chlamydia. You could also be exposed to the increased risk of sexual assault. Such behavior can have a devastating affect on your future.