Ketamine is noninferior to electroconvulsive therapy (ECT) for managing treatment-resistant depression, defined as depression that does not respond to 2 or more antidepressants, according to from a randomized clinical trial of 365 participants without psychotic symptoms. The drug is currently approved for use as a sedative, general anesthetic, and analgesic by the US Food and Drug Administration.

After 3 weeks, about 55% of participants who received twice weekly ketamine reported at least a 50% improvement in their depression symptoms compared with about 41% of participants who received ECT. During the 6-month follow-up period, about 35% of participants treated with ketamine and about 56% of those treated with ECT relapsed.