Hallucinogens. Coloured blotting paper and tablets. © Australian Drug Foundation, 2011.Hallucinogens facts

What are hallucinogens?

Effects of hallucinogens

Tolerance and dependence

Getting help

Hallucinogen use in Australia

What are hallucinogens?

Hallucinogenic drugs, also known as “psychedelics”, are drugs that change the way a person perceives the world. Hallucinogens affect all the senses, altering a person’s thinking, sense of time and emotions.

They can cause a person to hallucinate—seeing or hearing things that do not exist or are distorted. There are many different kinds of hallucinogens. Some occur naturally, in trees, vines, seeds, fungi and leaves. Others are made in laboratories.

Some examples of hallucinogens are:

  • LSD (lysergic acid diethylamide)
  • PCP (phencyclidine)
  • magic mushrooms (psilocybin)
  • ketamine
  • mescaline (peyote cactus)
  • morning glory seeds
  • datura.

LSD (lysergic acid diethylamide)

LSD is made from a substance found in ergot, which is a fungus that infects rye. It is a very powerful drug, so only very small doses are usually taken.

Other names

Acid, trips, tabs, microdots, dots.

What it looks like?

In its pure state, LSD is a white odourless powder. It usually comes in the form of squares of gelatine or blotting paper that have been dipped or soaked in LSD. LSD is also sold as a liquid, tablets or capsules.

How is it used?

LSD is usually swallowed, sniffed, injected or smoked.

Magic mushrooms (psilocybin)

There are several varieties of magic mushrooms. “Golden tops”, “blue meanies” and “liberty caps” are some of the types found in Australia that have the active ingredient psilocybin.

Street names

Shrooms, mushies, magics, golden tops, blue meanies, liberty caps.

What they look like?

Magic mushrooms look much like ordinary dried mushrooms, or they come as powdered material in capsules. Synthetic psilocybin appears as a white crystalline powder that may be processed into tablets or capsules, or dissolved in a liquid.

Mushrooms containing psilocybin can often look very similar to other mushrooms that are actually poisonous. Some poisonous mushrooms may cause permanent liver damage or death after being eaten.

How are they used?

Magic mushrooms are usually eaten fresh, cooked or brewed into a “tea”. Occasionally, they may be mixed with tobacco or cannabis and smoked.


Ketamine hydrochloride is a dissociative anaesthetic that is sometimes used in medical and veterinary settings.

Street names

Special K, K, ket, kitkat, super K.

What it looks like?

Ketamine is a white crystalline powder that can be made into tablets, or dissolved in liquid.

How is it used?

Ketamine is usually swallowed, snorted or injected. It is sometimes smoked with other drugs such as cannabis or tobacco.

Mescaline (peyote cactus)

Mescaline is the active ingredient of the peyote cactus, Lophophora williamsii. It can also be made synthetically.

Street names

Cactus, cactus buttons, cactus joint, mesc, mescal.

What it looks like?

In its pure state, mescaline sulphate is a white crystalline powder. Synthetic mescaline may appear as different coloured powders. The peyote cactus contains “buttons” that can be cut from the root of the plant and dried.

Effects of hallucinogens

The effects of any drug (including hallucinogens) vary from person to person. How hallucinogens affects a person depends on many things including their size, weight and health, also whether the person is used to taking it and whether other drugs are taken around the same time.

The effects of any drug also depend on the amount taken. This can be very hard to judge as the quality and strength of illicit drugs can vary greatly from one batch to another.

There is no safe level of drug use. Use of any drug always carries some risk—even medications can produce unwanted side effects. It is important to be careful when taking any type of drug.

Immediate effects

The effects of hallucinogens can last several hours and vary considerably, depending on the specific type of hallucinogen. Some of the typical effects of hallucinogens are:

  • feelings of euphoria
  • sense of relaxation and wellbeing
  • hallucinations and distorted perception, including visual, auditory, body, time and space
  • disorganised thoughts, confusion and difficulty concentrating, thinking or maintaining attention
  • anxiety, agitation, paranoia and feelings of panic
  • dizziness
  • blurred vision
  • loss of coordination
  • increased breathing rate
  • increased heart rate and blood pressure
  • irregular heartbeat, palpitations
  • nausea and vomiting
  • increased body temperature and sweating, may alternate with chills and shivering
  • numbness.

“Bad trips”

Sometimes a person may experience the negative effects of hallucinogens and have what is called a “bad trip”. They may experience some of the following:

  • unpleasant and/or intense hallucinations
  • anxiety
  • paranoia
  • panic or fear.

Feelings of panic, paranoia and fear can lead to risky behaviour that can cause injury, such as running across a busy street.

Some people may experience a drug-induced psychosis after using hallucinogens. This can occur after a single dose or long-term use. The psychosis is usually characterised by hallucinations, delusions and bizarre behaviour and can last for several hours or longer for some people.

Higher doses

High doses of hallucinogens can increase the negative immediate effects.

Deaths from an overdose of LSD, magic mushrooms and mescaline are extremely rare. A high dose of hallucinogen can cause a person to overdose. This means that a person has taken more hallucinogen than their body can cope with. Not knowing the strength or purity of the hallucinogen increases the risk of overdose.

Deaths generally occur due to suicide, accidents and dangerous behaviour, or due to the person inadvertently eating poisonous plant material. An overdose of PCP or ketamine can result in depressed breathing, coma, convulsions, seizures and death.

Coming down

As the effects of the hallucinogen begin to wear off a person may experience a range of effects. These effects can last for a number of days after use and may include:

  • depression
  • anxiety
  • panic attacks
  • psychosis.

Long-term effects

The most common long-term effect of hallucinogen use is the “flashback”. Flashbacks are a re-experience of the drug and can occur days, weeks, months and even years later.

Flashbacks can be triggered by the use of other drugs, or by stress, fatigue or physical exercise. The flashback experience can range from being pleasant to causing severe feelings of anxiety. They are usually visual and last for a minute or two.

Other effects of hallucinogen use

Social problems

All areas of a person’s life can be affected by drug use.

  • Disagreements and frustration over drug use can cause family arguments and affect personal relationships.
  • Legal and health problems can also add to the strain on personal, financial and work relationships.

Taking hallucinogens with other drugs

The effects of mixing hallucinogens with other drugs, including alcohol, prescription medications and over-the-counter medicines, are often unpredictable.

Mixing hallucinogens with stimulant drugs (such as cocaine or amphetamines) increases the stimulant effects and can further increase the heart rate and place the body under extreme stress.

Combining hallucinogens with depressant drugs such as alcohol may further reduce coordination and increases the chances of vomiting.

Pregnancy and breastfeeding

Read about the effects of taking drugs during pregnancy or breastfeeding.


It is dangerous to drive after using hallucinogens. The effects of hallucinogens, such as hallucinations and distorted perception, can affect driving ability.

Read more about the effects of drugs on driving.

Hallucinogen use in the workplace

Under occupational health and safety legislation, all employees have a responsibility to make sure they look after their own and their co-workers’ safety. The effects of hallucinogens and the symptoms of coming down and withdrawal can affect a person’s ability to work safely and effectively.

Tolerance and dependence

There is evidence that after prolonged use, hallucinogens can become addictive. People who use hallucinogens regularly can develop dependence and tolerance to them, which means they need to take larger amounts of hallucinogens to get the same effect.

People who are psychologically dependent on hallucinogens may find they feel an urge to use it when they are in specific surroundings or socialising with friends. There is a small risk of physical dependence from hallucinogens.


If a dependent person stops taking hallucinogens, they may experience withdrawal symptoms because their body has to get used to functioning without hallucinogens.

While severe physical symptoms are uncommon, hallucinogen withdrawal can cause problems such as:

  • cravings for hallucinogens
  • fatigue
  • irritability
  • reduced ability to experience pleasure.

Getting help


In Australia, there are many different types of treatments for drug problems. Some aim to help a person to stop using a drug, while others aim to reduce the risks and harm related to their drug use. Find out more about treatment.

What to do if you are concerned about someone’s hallucinogen use

If you are concerned about someone’s drug use, there is help available. Contact the alcohol and drug information service in your state or territory.

What to do in a crisis

Always call triple zero (000) if a drug overdose is known or suspected—and remember that paramedics are not obliged to involve the police.

If someone overdoses or has an adverse reaction while using hallucinogens, it is very important that they receive professional help as soon as possible. A quick response can save their life.

Visit the Better Health Channel to read St John Ambulance’s advice on drug overdose.

Hallucinogen use in Australia

According to the National Drug Strategy household survey, in 2010, 8.8% of Australians aged over 14 years had used hallucinogens (other than cannabis and ecstasy) at some stage in their life.

For more statistics about the use of hallucinogens in Australia, visit our Quick statistics page.

Are they legal?

Many hallucinogens are illegal in Australia.

Federal and state laws provide penalties for possessing, using, making, cultivating and selling some hallucinogens. However, driving under the influence of any hallucinogen is illegal. Penalties can include fines, imprisonment and disqualification from driving.

Some states and territories have programs that refer people with a drug problem to treatment and/or education programs where they can receive help rather than going through the criminal justice system.

Read more about hallucinogens and Australian law.

For legal advice specific to your situation contact a legal aid service in your state or territory.

National drug policy

Australia’s national drug policy is based on harm minimisation. Strategies to minimise harm include encouraging people to avoid using a drug through to helping people to reduce the risk of harm if they do use a drug. It aims to reduce all types of drug-related harm to both the individual and the community.