Ketamine: an update on its abuse.

Ketamine is a dissociative anesthetic and substance of abuse. Numerous effects can result from the abuse of ketamine. Death from acute direct toxicity is rare. Ketamine can alter numerous functions in the brain including color perception, memory, attention, cognition, reaction time, and sense of time and can produce psychological addiction. Chronic ketamine abuse can produce toxicity to the gastrointestinal and urinary tract. Gastrointestinal changes include epigastric pain, hepatic dysfunction, and impaired gallbladder activity. The most common urological condition from ketamine is cystitis but renal failure has been reported.