What is it?
Ketamine is a licensed anaesthetic medicine that is also used illicitly for its dissociative effects.
Common forms
- Powder
- Liquid
- Tablets
How it affects the body
Ketamine acts mainly on NMDA receptors, producing dissociation, altered perception and reduced pain sensation.
Short-term effects
- Dissociation and altered perception
- Reduced coordination and pain awareness
- Nausea
- Confusion or distress at higher amounts
Long-term effects
- Bladder and urinary tract damage, which can be severe
- Abdominal pain
- Memory and concentration problems
- Dependence
Dependence and addiction
Dependence can develop when the body and brain adapt to regular use. It is not a moral failing or a lack of willpower. Signs people describe include needing more to get the same effect, difficulty cutting down, spending more time thinking about use, and continuing despite harm. Support is available at any stage — you do not need to have reached a crisis point.
Withdrawal
Stopping or reducing after regular use can cause withdrawal. Withdrawal varies between people and depends on how much and how long someone has used, their physical health and other substances involved. Some withdrawal can be medically serious, so it is safer to plan a reduction with a clinician or a drug and alcohol service rather than stopping abruptly alone.
Overdose risks
Unresponsiveness, difficulty breathing, or being unable to rouse someone are emergencies. Because pain is dulled, injuries can go unnoticed. Call 999.
Mixing substances
Combining with alcohol or other depressants increases the risk of unconsciousness and choking.
Harm-reduction information
- Never use alone or in water
- Seek medical advice early for urinary pain or blood in urine
- Avoid mixing with alcohol or other sedatives
- Stay with people who can help if you become unresponsive
When to seek urgent medical help
Call 999 if someone is unconscious or cannot be woken, is having difficulty breathing, has a seizure, has chest pain, becomes very confused or agitated, or you are worried they may have overdosed. For urgent advice that is not life-threatening, call NHS 111. You will not get someone into trouble by calling for medical help.
Treatment and recovery options
- Talking therapies and structured psychosocial support
- Community drug and alcohol services, including self-referral where available
- Medication-assisted treatment where clinically appropriate
- Medically supported withdrawal, arranged and monitored by clinicians
- Peer support and recovery communities
- Residential rehabilitation for some people, usually via assessment
- Support for related needs — mental health, housing, family and welfare
UK support resources
- NHS — health information and service finders (nhs.uk)
- Talk to FRANK — UK drug information service (talktofrank.com)
- Your local community drug and alcohol service — many accept self-referrals
- Local pharmacy teams, who can offer advice and signposting
Sources / references
This page is a plain-language summary written for education. For clinical or legal detail, use authoritative UK sources: NHS (nhs.uk), Talk to FRANK (talktofrank.com), NICE (nice.org.uk), UK Government and devolved government publications, and guidance from UK professional bodies. Each page on this site carries a review date, and we welcome corrections.