K-cramps are a medical term used to refer to intense abdominal discomfort associated with regular use of ketamine. Is not an official medical diagnosis. The pain is often severe and may result in vomiting or nausea. Evidence for abdominal and hepatobiliary effects commonly seen as late long-term consequences of chronic ketamine use is now recognised in the UK.
The source of this is not completely known. Changes in liver and bile duct in some cases may be due to the change or other abdominal symptoms may be linked to different causes. That’s why severe or recurring stomach pain should not be taken for granted to be K-cramps.
What does “K-cramps” mean?
Some people who regularly use ketamine experience abdominal pain, and the term “K-cramps” refers to that. It’s most commonly used to refer to the non-medical (or non-therapeutic) use of ketamine, specifically for reasons other than medical treatment. It is not the name of a disease or a specific category of abdominal issues.
An advisory council on the Misuse of Drugs (ACMD) report indicates that the longer ketamine users use drugs, the more they report chronic abdominal pain, sometimes accompanied by vomiting. Generally, the pain occurs around the upper abdomen and the epigastric area. It could be coming and going rather than constant.
Studies have also revealed that the abdominal symptoms may be accompanied by other issues resulting from the use of ketamine such as damage to the urinary system. This indicates that an individual can have multiple health issues at once.
What does the pain feel like?
No single pattern is diagnostic of K-cramps. The pain can be described as involving the upper abdomen, severe cramping or aching. It may be accompanied by nausea and vomiting.
There are some published reports that they experience pain inside their stomach, also known as epigastric pain. A review of evidence in the UK revealed the possibility of vomiting recurring with these symptoms.
The key aspect is that the sensation of the pain can’t tell you what is causing the pain. A number of disorders can cause high-grade abdominal pain, including gallstones, pancreatitis, stomach disease, infections and others. The NHS advises against self-diagnosing a stomach ache that persists or worsens, so don’t try to self-diagnose.
Why can ketamine cause abdominal pain?
There is still ongoing research about what causes K-cramps. Evidence has shown that ketamine can adversely impact the gastrointestinal system, as well as the liver and biliary system, particularly when used frequently or for extended periods.
Ketamine and its metabolites may be metabolized and eliminated from the body in a manner that could be hepatotoxic to the bile ducts. Chronic-ketamine users have been found to have bile-duct widening and other abnormalities in studies. Not all abdominal pain is due to harm to the bile-ducts.
The ACMD’s 2026 review also says it remains unclear whether some abdominal symptoms are caused directly by gastrointestinal toxicity or are related to changes in the liver and biliary tree.
Is every stomach pain episode caused by ketamine?
Abdominal pain can have many causes and can occur in someone using Ketamine for a different reason as it can in others. Possible causes of abdominal pain listed in the NHS guidance include trapped wind, constipation, stomach infections, gallstones, kidney stones and appendicitis. There are certain reasons that require an instant response.
This is important because if pain is considered to be just “K-cramps” there might be a delay in receiving adequate medical evaluation. A healthcare provider might enquire about the place and time that the pain manifests, vomiting, bowel and urinary symptoms, medicines and drug usage. Depending on the symptoms, blood tests or scans could be required.
Clinicians can think about the appropriate cause or tests when they know that the patient is using ketamine. Medical information is confidential and accurate information regarding drug use may be crucial for diagnosis of unusual symptoms.
Connection with liver and bile-duct Complications
One of the less positive ones is the association between chronic use of ketamine and hepatic and biliary disorders. The bile ducts carry bile from the liver towards the digestive system. If any of these ducts become irregularly enlarged, this can alter the flow of the bile.
According to the “2026 ACMD review, chronic liver injury and chronic bile-duct dilation” have been reported in association with regular use of ketamine. Other longer-term effects have also been associated with liver fibrosis and, at the extreme, cirrhosis.
A systematic review of published cases found that abdominal pain, nausea and vomiting were common symptoms among people with ketamine-related biliary disease. One of the imaging techniques occasionally revealed a dilated common bile duct.
Previous studies also showed that the severity of bile duct enlargement was associated with severity of ketamine use. Ketamine was found to be effective when discontinued in some patients.
The findings do not indicate that all persons who may have abdominal pain have liver or bile-duct damage. They demonstrate why it is appropriate to allow symptoms to be assessed with appropriate medical history.
When pain needs urgent assessment
If the abdominal pain is bad, it is not something that needs to be ignored especially if it comes out abruptly or worsens. NHS guidance recommends emergency help for sudden or severe stomach pain, pain that hurts when the abdomen is touched, vomiting blood, black or bloody stools, inability to pass urine, breathing problems or collapse.
Another sign of great concern is that the eyes or skin turns yellow. This is known as jaundice, and may sign a liver or bile-duct problem. Official NHS guidance says that if jaundice does occur it is a sign that urgent medical help is needed.
If the vomiting doesn’t stop, the temperature is high, the pain gets worse or is recurring, medical advice is required. NHS 111 must be able to help you gauge your symptoms and guide you to the best service in England. In cases of emergency contact 999 or attend A&E.
Can symptoms improve?
They can. It appears some bile duct and abdominal changes seen with ketamine may result in better resolution when ketamine exposure is discontinued, especially if abnormalities are detected early. Early hepatobiliary abnormalities may resolve upon withdrawal of the drug, and longer lasting damage can be permanent, according to the ACMD review.
There has also been research on the beneficial effects of stopping ketamine on improving bile-duct abnormalities in some individuals. But recovery is not always assured and if there is damage to the liver or bile-duct an appropriate medical remedy may be necessary.
If abdominal pain is recurring, it is advisable to seek help from a health care provider rather than attempt to treat it on their own.
Why repeated episodes should not be ignored
There can be many different reasons for abdominal pain. A pattern of repeated use in a person who is persistent in his or her use of ketamine is different because it may indicate a continuing health issue.
Chronic abdominal pain is also a common problem among people who use ketamine regularly, says the ACMD, and it seems there may be more risk in people who use the drug for longer periods and greater quantities.
Repeated pain can also occur alongside liver, bile-duct or urinary problems. This assessment provides an opportunity for clinicians to recognize them early and prevent them from progressing to more severe issues.
However, when used in a medical setting by trained and authorized health care professionals, ketamine has also legitimate uses. The risks outlined here are primarily related to non-medical use of the drug when used frequently or for a long period, and are not intended as a medical prescription.
References
https://www.nhs.uk/nhs-services/urgent-and-emergency-care-services/when-to-use-111
https://pubmed.ncbi.nlm.nih.gov/38431685
Evidence last checked: 20 September 2026
