ketamine and syringe

Last published: November 19, 2020

What is ketamine?

Ketamine is used by medical practitioners and veterinarians as an anaesthetic. It is sometimes used illegally by people to get high.

Ketamine can produce psychedelic effects, causing a person to see, hear, smell, feel or taste things that aren’t really there or are different from how they are in reality.

When it’s sold illegally, ketamine usually comes as a white crystalline powder. It can also be made into tablets and pills, or dissolved in a liquid.1

A number of clinical trials and studies are currently being undertaken to assess ketamine as a treatment for depression, early indications are showing good results.

Other names

Special K, K, ket, kitkat, super k, horse tranquilliser or horse trank.2,3

Other types of dissociatives

How is it used?

Ketamine can be swallowed, snorted or injected. It is also sometimes smoked with cannabis or tobacco. The effects of ketamine may be experienced within 30 seconds if injected, 5–10 minutes if snorted, and up to 20 minutes if swallowed. The effects of ketamine can last for approximately 45 to 90 minutes.3

Effects of ketamine

There is no safe level of drug use. Use of any drug always carries some risk. It’s important to be careful when taking any type of drug.

Ketamine affects everyone differently, based on:

  • size, weight and health
  • whether the person is used to taking it
  • whether other drugs are taken around the same time
  • the amount taken
  • the strength of the drug (varies from batch to batch).

The following effects may be experienced:

  • feeling happy and relaxed
  • feeling detached from your body (‘falling into a k-hole’)
  • hallucinations
  • confusion and clumsiness
  • increased heart rate and blood pressure
  • slurred speech and blurred vision
  • anxiety, panic and violence
  • vomiting
  • lowered sensitivity to pain.2,3,5


If you take a large amount or have a strong batch, you could overdose. Call an ambulance straight away by dialling triple zero (000) if you have any of these symptoms (ambulance officers don’t need to involve the police):

  • inability to move, rigid muscles
  • high body temperature, fast heartbeat
  • convulsions
  • coma and ‘near death’ experiences
  • death.2,3,5

Coming down

In the day following ketamine use, you may be experience:

  • memory loss
  • impaired judgement, disorientation
  • clumsiness
  • aches and pains
  • depression.2,3,5

Long-term effects

Regular use of ketamine may eventually cause:

  • headaches
  • flashbacks
  • poor sense of smell (from snorting)
  • mood and personality changes, depression
  • poor memory, thinking and concentration
  • ketamine bladder syndrome (see below)
  • abdominal pain
  • needing to use more to get the same effect
  • dependence on ketamine
  • financial, work and social problems.2,3,5

Ketamine bladder syndrome

Large, repeated doses of ketamine may eventually cause ‘ketamine bladder syndrome’, a painful condition needing ongoing treatment. Symptoms include difficulty holding in urine, incontinence, which can cause ulceration in the bladder. Anyone suffering from ketamine bladder syndrome needs to stop using ketamine and see a health professional.2,5

Using ketamine with other drugs

The effects of taking ketamine with other drugs– including over-the-counter or prescribed medications – can be unpredictable and dangerous, and could cause:

  • Ketamine + alcohol or opiates: lack of awareness of effects of the depressant drugs, which may lead to taking too much and vomiting, slowed breathing, coma and death.5
  • Ketamine + amphetamines, ecstasy and cocaine: enormous strain on the body, which can lead to fast heart rate.2


Giving up ketamine after using it for a long time is challenging because the body has to get used to functioning without it. Withdrawal symptoms usually last for 4-6 days. These symptoms can include:

  • cravings for ketamine
  • no appetite
  • tiredness
  • chills, sweating
  • restlessness, tremors
  • nightmares, anxiety, depression
  • irregular and rapid heartbeat.2

Getting help

If your use of ketamine is affecting your health, family, relationships, work, school, financial or other life situations, you can find help and support.

Call 1300 85 85 84 to speak to a real person and get answers to your questions as well as advice on practical ‘next steps’.

You can also search our list of Support Services for services in your local area:

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Legally produced ketamine is a restricted substance and only a doctor or vet may prescribe or administer it. All other ketamine is illegal in Australia.

Federal and state laws provide penalties for the illegal use, possession, production, selling or driving under the influence of ketamine. Penalties can include fines, imprisonment and disqualification from driving.

See also, drugs and the law.


  • 1.9% of Australians aged 14 years and over have used ketamine one or more times in their life.7
  • 0.4% of Australians aged 14 years and over have used ketamine in the previous 12 months.7

Young people

  • Young Australians (aged 14–24) first try ketamine at 19.4 years on average.7
  1. Drug Enforcement Administration. (n.d.). Ketamine  [Fact sheet].
  2. Morgan, C., & Curran, H. (2011) Ketamine use: a review. Addiction, 107(1).
  3. Center for Substance Abuse Research. (2013). Ketamine.
  4. Winstock, A., & Wolff, K. (2006). Ketamine: from medicine to misuse. Central Nervous System Drugs, (20)3.
  5. DrugWise. (n.d.). Ketamine [Fact sheet].
  6. Zarate, C. & Niciu, M. (2015). Ketamine for depression: evidence, challenges and promise. World Psychiatry. 14(3), p. 348-350.
  7. Australian Institute of Health and Welfare. (2017). National Drug Strategy Household Survey detailed report 2016. Canberra: AIHW.

Explore dissociatives on the Drug Wheel

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anxiety, blurred vision, clumsiness, confusion, feeling detached from your body, feeling happy, feeling relaxed, hallucination, increased blood pressure, lowered sensitivity to pain, panic, slurred speech, violence, vomiting


K, horse trank, k-hole, ket, kitkat, special K, super k