Ketamine is a drug used for anesthesia. People who use it illicitly may snort it or inject it intravenously, into a muscle, or under the skin.
Ketamine reduces pain perception and causes giddiness and euphoria, which are often followed by bursts of anxiety. With high doses (overdose), users have a distorted perception of their body, the environment, and time. They feel scattered or as if they are not real (called depersonalization), and they feel detached from their environment (called dissociation).
At even higher doses, hallucinations and paranoid delusions may occur, and the sense of detachment from the world intensifies. Ketamine users often refer to these experiences as a k-hole. People may become combative. Coordination may be lost, and muscles tremble and jerk.
Very high doses may cause a life-threatening high body temperature (hyperthermia), a fast heart rate, very high blood pressure, seizures, and coma. Ketamine can also disrupt memory for several hours.
Diagnosis and Treatment
No test can rapidly confirm the presence of ketamine in the body.
Usually, reassurance and a quiet, nonthreatening environment help people recover. Benzodiazepines (sedatives) can be used to control seizures. Ketamine's effects usually abate in about 30 minutes.
Last full review/revision January 2009 by Patrick G. O'Connor, MD, MPH