“It’s early, but this is exciting because this gives us a new target, and it’s a heck of a first move on it,’’ said Raymond DePaulo, chief of the Department of Psychiatry at Johns Hopkins School of Medicine and one of the nation’s preeminent researchers on depression. He was not involved in the ketamine trials. “This is working on ... a different set of chemicals. It says the malfunction may be in several different parts of the brain. Ketamine has potential negative effects, but we could create 100 drugs to hit this target of glutamate.’’

Says Peter Kramer, author of Listening to Prozac and clinical professor of psychiatry and human behaviour at Brown University: “Prozac wasn’t effective at more major depressions, but only with more minor forms. I think the field is very much waiting for the next breakthrough.’’

No one thinks your family doc will be writing you a script for ketamine any time soon, but research continues. Zarate said the next step is developing counter-medications to mask ketamine’s side effects, then on to other medicines that target glutamate. We’re talking years here.

—Washington Post / Neely Tucker