Ketamine, widely abused as a party drug and sometimes called as "Special K," can cause inflammation and contraction of the bladder leading to possibly irreversible kidney damage, according to a report from Hong Kong.
Ketamine is mostly used as a veterinary anesthetic. In humans, it causes hallucinations and high blood pressure. It became widely abused in some parts of the world by the 1990s, and has since been banned or classified as a controlled substance in several countries.
"Street-ketamine abuse is not only a drug problem but might be associated with a serious urological condition causing a significant burden to healthcare resources," Dr. Peggy Sau-Kwan Chu and colleagues write in the medical journal BJU International.
In their study, Chu, from Tuen Mun Hospital, Hong Kong, China, and others describe problems that developed in 59 ketamine abusers who were seen at Hong Kong hospitals from March 2000 to December 2007.
All of the subjects had moderate to severe lower urinary tract symptoms, such as urgency, frequency, and difficulty urinating.
Visual examination with a cystoscope revealed an inflamed bladder in 42 of these individuals, and biopsies showed that 12 of them had a more serious condition called interstitial cystitis.
On further testing, 47 patients were found to have overactive bladder or decreased bladder elasticity, the team reports.
Damage to one or both kidneys was seen on ultrasound in 30 patients, and four of them had areas of dead kidney tissue.
"Abstinence from ketamine abuse is strongly advocated before any irreversible damage to the urinary tract occurs," Chu and her colleagues emphasize.
People who've used ketamine recreationally should seek early urological assessment, they advise. This may "help to reduce not only the detrimental effects to the abusers, but also the health costs to society."