The effects of ketamine typically last between 30 minutes to 1 hour, depending on the dose and route of administration. When injected intravenously, the onset is rapid (within seconds), and effects last about 5 to 15 minutes; when taken by other routes, effects may last up to an hour
. Ketamine has a half-life of approximately 2.5 hours, meaning that half of the drug is metabolized and eliminated from the body in this time. It generally takes about 10 to 12.5 hours (4 to 5 half-lives) for ketamine to be effectively cleared from the system
. However, ketamine and its metabolites can be detected in the body for much longer periods depending on the testing method:
- Saliva: up to 24 hours
- Blood: 1 to 3 days
- Urine: up to 14 days, with some studies suggesting detection up to 30 days
- Hair: up to 3 to 4 months after a single use
In summary, while the immediate psychoactive effects last about 30 to 60 minutes, ketamine remains in the body and can be detected by various tests for days to months after use.
