Last published: January 10, 2023
What is ketamine?
Ketamine is used by medical practitioners and veterinarians as an anaesthetic. It’s sometimes used illegally by people to get high.
Ketamine is a dissociative drug, which means it acts on different chemicals in the brain to produce visual and auditory distortion, and a detachment from reality.
When it’s sold illegally, ketamine usually comes as a white or off-white powder. It can also be made into pills, or dissolved in a liquid.1
Clinical trials and studies are assessing ketamine as a treatment for depression. Early indications show good results.2
Special K, K, ket, kitkat, super k or horse trank.3,4
How is it used?
Ketamine can be swallowed, snorted or injected. It’s also sometimes smoked with cannabis or tobacco. The effects of ketamine may be experienced within one minute if injected, 5–15 minutes if snorted, and up to 30 minutes if swallowed. Its effects can last for around an hour, however an individual’s coordination or senses may be affected for up to 24 hours after initial use.4
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’)
- visual and auditory hallucinations
- confusion and clumsiness
- increased heart rate and blood pressure
- slurred speech and blurred vision
- anxiety, panic and violence
- lowered sensitivity to pain3,4,6
If you take a large amount of ketamine or have a strong batch, you could overdose.
The risk of death from ketamine alone is low, due to its ability to cause unconsciousness with minimal impact on airway reflexes or blood circulation.5 However, individuals are at a higher risk of physical harm/accidents while under the influence of the ketamine.5
Call an ambulance straight away by dialling triple zero (000) if you or someone else has any of these symptoms (ambulance officers don’t need to involve the police):
- inability to move, rigid muscles
- high blood pressure, fast heartbeat
- unconsciousness and ‘near death’ experiences
- death. 3,6,5
The day after using ketamine, you may experience:
- memory loss
- impaired judgement, disorientation
- aches and pains
Regular use of ketamine may eventually cause:
- poor sense of smell (from snorting)
- mood and personality changes, depression
- poor memory, thinking and concentration
- abnormal liver or kidney function
- ketamine bladder syndrome (see below)
- abdominal pain
- needing to use more to get the same effect
- dependence on ketamine
- financial, work and social problems3,6
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.3
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: When used with other depressant drugs, the combined effects may lead to the functioning of the heart or lungs to slow or stop, and can result in death.68
- Ketamine + amphetamines, ecstasy and cocaine: enormous strain on the body, which can lead to fast heart rate.3,8
‘Polydrug use’ is a term for the use of more than one drug or type of drug at the same time, or one after another. Polydrug use can involve both illicit drugs and legal substances, such as alcohol and medications. Find out more about polydrug use.
Giving up ketamine after a long time is challenging because the body has to get used to functioning without it. Please seek advice from a health professional. Symptoms include:
- cravings for ketamine
- no appetite
- chills, sweating
- restlessness, tremors
- nightmares, anxiety, depression
- irregular and rapid heartbeat
- risk of inujry3
If your use of ketamine is affecting your health, family, relationships, work, school, financial or other life situations, or you’re concerned about a loved one, you can find help and support.
Call 1300 85 85 84 to speak to a real person and your questions answered as well as advice on practical ‘next steps’. It’s confidential too.
Not sure what you are looking for? Try our intuitive Path2Help tool and be matched with support information and services tailored to you.Find out more
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.
- 3.1% of Australians aged 14 years and over have used ketamine one or more times in their life.9
- 0.9% of Australians aged 14 years and over have used ketamine in the previous 12 months.9
- Young Australians (aged 14–29) first try ketamine at 20.4 years on average.9
- United States Drug Enforcement Agency Administration. Ketamine 2020 [03.06.2021].].
- Zarate C Niciu M. Ketamine for depression: evidence, challenges and promise. World Psychiatry. 2015;14(3):348–50.
- Morgan C Curran H. Ketamine use: a review. Addiction 2011;107(1).
- Darke S, Lappin, J. & Farrell, M. The Clinician's Guide to Illicit Drugs. United Kingdom: Silverback Publishing 2019.
- Kalsi S Wood D Dargan P. The epidemiology and patterns of acute and chronic toxicity associated with recreational ketamine use. Emerging Health Threats Journal 2011;4.
- Li L and Vlisides P. Ketamine: 50 Years of Modulating the Mind. Frontiers In Human Neuroscience 2016;10.
- Winstock A and Wolff K. 2006. Central Nervous System Drugs. Ketamine: from medicine to misuse;20(3).
- Janssen-Cilag Pty Ltd. Australian Product Information SPRAVATO® esketamine hydrochloride NSW 2021 [10.06.2021].
- Australian Institute of Health and Welfare. National Drug Strategy Household Survey 2019 2020 [09.09.2020].