Aug. 21, 2018 -- Ketamine, a widely used anesthetic that’s also an illicit party drug, has taken on a new role in recent years: treating severe depression in people who have not responded to standard treatment. Researchers have called it the most exciting breakthrough in the field of depression research in the past half-century.

One form of the drug, being developed as a nasal spray called esketamine, is in the final stages of testing needed before it can go to the FDA for approval.

It has not yet been approved by the FDA in any form to treat depression, but doctors may, and do, use it “off label” to treat depression and pain. Yet many questions about its safety and effectiveness remain unanswered.

“There’s still a lot to learn before we can use ketamine on a wide scale,” says Yale professor of psychiatry Gerard Sanacora, MD, PhD, who directs the Yale Depression Research Program in New Haven, CT. “But it seems to offer real benefits, even targeting suicidal thinking, which could be lifesaving.”