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Ketamine can cause hallucinations and can affect the body’s senses.

Ketamine can cause hallucinations and can affect the body’s senses.
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5-minute read

What is ketamine?

Ketamine is a medicine used by doctors and vets as a pain killer. It stops the brain from interpreting pain messages. It is being studied as a medication for depression.

It is also used illegally for its hallucinogenic ‘high’ effect. If bought illegally, it comes as a white powder that can be made into tablets or dissolved into a clear liquid. It can be swallowed, snorted, injected, inserted anally, or smoked with cannabis or tobacco. Sometimes it’s sold as ecstasy. It is sometimes used to spike people’s drinks.

It’s also known as special K, ket, kitkat, super K and horse trank.

What are the effects of taking ketamine?

Ketamine takes effect within 30 seconds to 20 minutes, depending on how it’s taken. The effects can last for 45 to 90 minutes.

Users experience a high in which they may feel happy and relaxed. They may also feel detached from their body (knowns as falling into a k-hole). People who take ketamine can have hallucinations. It alters their perception of reality. They can see, hear, smell or taste things that don’t exist, or can perceive them differently to how they really are.

While the high might feel good, there are downsides too. While using ketamine, people can have blurred vision, slurred speech, become physically uncoordinated, sweat, have a raised temperature and heart rate, feel nauseous and vomit.

When using it, people can:

  • feel disorientated and drowsy
  • have hallucinations
  • feel numb
  • feel uncoordinated
  • become panicked, confused and anxious
  • have a near-death experience

In the days after taking ketamine, people may feel depressed, clumsy, have memory loss or be disoriented, or suffer aches and pains.

Ketamine can affect people differently based on:

  • how much they take
  • how strong it is
  • their size, height and weight
  • whether they are used to taking it
  • whether they take other drugs at the same time

Find out more about how drugs and alcohol can impact your health, including where to find help and support.

What can go wrong with ketamine?

If people overdose, they can have convulsions, go into a coma and die. The signs someone has overdosed on ketamine include:

  • they can’t move
  • their muscles are rigid
  • they have convulsions

If you think someone has overdosed on ketamine, call triple zero (000) for an ambulance. Ambulance officers don’t have to call the police.

Can ketamine cause long-term problems?

People who use ketamine long term can develop headaches, stomach pain and what is known as ketamine bladder syndrome. This is a painful condition with incontinence and ulcers in the bladder. It needs long term treatment and can lead to kidney problems.

Regular users can have:

  • flashbacks
  • mood and personality changes
  • depression
  • problems with memory and concentration
  • psychosis

Regular users are also more likely to have social, work and financial problems.

What if I use other drugs or alcohol together with ketamine?

People are more likely to overdose if they take ketamine with alcohol, heroin or other opiates.

Taking ketamine with amphetamines, ecstasy or cocaine puts strain on the body and leads to a fast heart rate.

Can I become dependent on ketamine?

People who use ketamine regularly can become tolerant – they need more of the drug to achieve the same effects. It is also possible to develop dependence to ketamine, making it hard to stop. People coming off ketamine may have symptoms for 4 to 6 days, including:

  • cravings
  • not wanting to eat
  • feeling lethargic
  • chills and sweats
  • nightmares
  • feeling anxious, restless and depressed
  • the shakes
  • a fast and irregular heartbeat

Resources and support

Find information about cocaine on the Alcohol and Drug Foundation website or by calling DrugInfo on 1300 85 85 84.

You can find help on the Drug Help website or by calling the National Alcohol and Other Drug Hotline on 1800 250 015. You can also call Lifeline on 13 11 14.

If you or someone you know are finding it difficult to manage issues as a result of drug use, try healthdirect’s Symptom Checker and get advice on when to seek professional help.

The Symptom Checker guides you to the next appropriate healthcare steps, whether it’s self care, talking to a health professional, going to a hospital or calling triple zero (000).

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: January 2021

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