Epidural ketamine. A preliminary report.

Ketamine hydrochloride 4 mg in 10 ml 5% dextrose water was administered epidurally to 7 patients suffering from intractable pain in the back, lower abdomen and legs. Pain relief was obtained in all cases. The duration of action varied from half an hour to more than 6 hours. No adverse side-effects were noted and no detectable neurological damage resulted. Intraspinal ketamine offers and advantage over the opiates, in that respiratory depression is unlikely to occur.