Ketamine is an anaesthetic that doctors and vets use for sedation and pain relief, but sold illegally it is taken for its detached, dreamlike high. Regular use can lead to addiction and to a painful kind of bladder damage, and in Malaysia using it is a criminal offence under the Dangerous Drugs Act 1952. The good news is that people do stop, and the bladder often improves gradually once they stay off it.
This guide explains what ketamine does, the warning signs of a problem, what stopping feels like and where adults in Malaysia can get help.
What ketamine is and what it does
In hospitals, ketamine is used as a sedative and pain reliever. Outside medicine it is usually a white powder that is snorted, and it can be slipped into drinks. Effects start within seconds to about 20 minutes and last up to three hours.[1]
People describe feeling numb, floaty and cut off from their body and surroundings. Speech slurs, vision blurs and movement becomes clumsy. Larger amounts can bring hallucinations and the "k-hole", a state where the person can hardly move or speak. The same effects can turn into panic, confusion, a racing heart and vomiting.
Because pain is dulled and coordination is poor, people on ketamine can hurt themselves without noticing. Falls, accidents and choking on vomit are real risks.
Why mixing ketamine with other drugs is dangerous
Ketamine is rarely the only drug in the picture. In Malaysia it turns up alongside other pills: in June 2026 police in Ipoh seized about a kilogram of ketamine together with more than a kilogram of Erimin 5.[9]
- With alcohol, sleeping pills, Erimin 5, heroin or other opioids, ketamine can slow breathing and the nervous system. People can pass out, choke on vomit or die.
- With syabu, ecstasy or other stimulants, it puts extra strain on the heart.
- Unknown pills and powders may contain something other than what the seller claims.
If someone cannot be woken, is breathing slowly or noisily, or is having a fit, call 999 straight away and tell the crew everything they took.
Ketamine bladder: the damage people do not expect
The harm most specific to ketamine is to the bladder and urinary tract. Health services call it ketamine bladder syndrome. With regular use, the bladder lining becomes inflamed and can ulcerate. Signs include:[4]
- needing to pass urine very often and very urgently
- pain in the lower belly or when passing urine
- blood in the urine
- leaking urine or not being able to hold it in
In severe cases the kidneys are affected too, and a small number of people have needed their bladder removed. Up to a third of long-term users also get intense stomach pain, sometimes called "K cramps".[5]
The most important point is this: stopping is the main treatment. A ten-year review from Hong Kong, where ketamine bladder was common, found that people who had stayed off ketamine for a year had much less pain and urgency than people still using. Improvement is gradual, and using again tends to bring the symptoms back. Anyone with these symptoms should see a doctor soon. Do not try to manage the pain by using more ketamine or other drugs.[6]
Ketamine and the mind
Long-term use is linked to poor memory and concentration, low mood, depression and changes in personality. Heavy use can cause flashbacks and, especially in people with a history of mental illness, psychotic symptoms such as paranoia or hearing things. Our guides to how drugs affect the brain, drug-induced psychosis and depression and addiction explain these links.[2]
You may have read about ketamine being studied for depression. That research uses controlled medical doses under a specialist, often as a nasal spray. It is not the same as street ketamine, and street use carries all the harms on this page.
Signs that ketamine use has become a problem
Ketamine dependence is recognised by health services. Tolerance builds quickly, so people need more for the same effect. Signs of a problem include:
- using more often, or more each time, than planned
- feeling that you need it to socialise, work or get through the day
- trying to cut down and not managing
- spending money you cannot afford, or hiding how much you use
- carrying on despite bladder pain, stomach cramps or low mood
- falling behind at work or pulling away from family
For families, the signs can be vague: frequent trips to the toilet, clumsiness, long spells of seeming "switched off", money going missing. Our guide to the signs of drug use covers what to look for.
What stopping ketamine feels like
Stopping after regular use is hard, but the physical side is usually milder than with alcohol, sleeping pills or heroin. Withdrawal symptoms tend to last about four to six days and can include:
- strong cravings
- tiredness, poor appetite and poor sleep
- sweating, chills, shaking and restlessness
- anxiety, low mood and nightmares
- a fast or irregular heartbeat
Cravings and low mood can last longer than the physical symptoms, which is why many people relapse in the weeks after stopping. If you also use alcohol, sleeping pills, Erimin 5 or other sedatives, do not stop those suddenly on your own: withdrawal from them can cause seizures and needs a doctor. Our guide to drug withdrawal symptoms has more.
Treatment that helps
There is no medicine that cures ketamine addiction. What helps is a combination of:
- a medical check, including the bladder and kidneys, and treatment for pain and any other health problems
- talking therapy, such as cognitive behavioural therapy, to understand what drives the use and to handle cravings
- support for mental health, because depression and anxiety often sit underneath
- time away from the people and places linked to using, which is where residential care can help
- family involvement and a plan for after treatment
Ketamine and the law in Malaysia
Ketamine is controlled under the Dangerous Drugs Act 1952. Using it is an offence under Section 15(1)(a), with a fine of up to RM5,000, up to two years in jail, or both, followed by police supervision. Trafficking falls under Section 39B, which carries the heaviest penalties in Malaysian law, and courts have handed down death sentences for large ketamine seizures. Our guide to drug laws in Malaysia explains more, and how long drugs stay in your system covers drug tests.[8][7]
Getting help is treated differently from being caught. Since the amended Act 283, adults can go to AADK themselves for free, confidential voluntary treatment. Our guide to voluntary drug rehab in Malaysia explains how it works.[11]
Common questions
Is ketamine addictive?
Yes. Health services describe an established ketamine dependence and withdrawal syndrome, and tolerance builds quickly. Many people who use it regularly find it hard to stop.[3]
Can ketamine bladder damage be reversed?
Often it improves, slowly, once a person stops for good. A Hong Kong review found less pain and urgency after a year without ketamine. Severe damage may need long-term treatment, so see a doctor early.
How long does ketamine withdrawal last?
The physical symptoms usually last about four to six days. Cravings, poor sleep and low mood can go on for weeks, which is when support matters most.
Is ketamine legal in Malaysia?
Only as a medicine used by doctors and vets. Using it otherwise is an offence under the Dangerous Drugs Act 1952, and trafficking carries very heavy penalties.
Someone I love uses ketamine. What can I do?
Talk to them calmly when they are sober, about specific things you have noticed, and offer a concrete next step. Our guide on how to help someone with drug addiction walks through it.
Getting help
If you or someone close to you wants to stop ketamine, you have options. AADK's voluntary route is free. A private drug rehabilitation centre in Malaysia offers a residential stay away from the triggers of everyday life. Our page on choosing an addiction rehab centre in Malaysia explains what to look for, and the Malaysian drug statistics guide shows how common drug problems are.
Salus is a voluntary 90-day residential programme for adults aged 18 and over in Cyberjaya, with therapy delivered alongside medical care. If you would like to talk it through, contact us for a free, confidential conversation.
This article is general information, not medical advice. In an emergency, call 999.
