For years, physicians have been inching their way to a better understanding of how -- and how well -- the drug ketamine, a "twilight drug" used to sedate some patients before a painful procedure, can lift someone with severe depression almost immediately from the abyss.
A new study, presented in San Francisco this week at the American Psychiatric Association's yearly meeting, shows that ketamine's rapid antidepressant effect is no incidental effect of sedation: it's real, and it lasts -- albeit with diminishing effects -- for at least a week.
Ketamine, which is also a drug used recreationally to achieve a sort of "out of body" high, "is not at all ready for prime time," said Dr. James Murrough, an associate professor of psychiatry at Icahn School of Medicine at Mt. Sinai. But it is approved for use in anesthesia, so it's available legally. And years of small and preliminary trials have offered tantalizing evidence of its powerful and fast-acting antidepressant effect on patients whose depression has failed to yield to other treatments.
The result, said Murrough, is that some physicians appear to be using it already in patients.
"That reflects desperation out there" for antidepressant medicine that does not take between four and six weeks to take effect, as is the case for many patients with the most widely used class of antidepressants, the Selective Serotonin Reuptake Inhibitors (SSRIs). But the fact that ketamine is already being used off-label makes good clinical research on its safety and effectiveness a matter of urgency, said Murrough.