U Research: Surgical Anesthetic Appears to Treat Drug-Resistant Depression

Jul 29, 2013

Researchers at the University of Utah are exploring an alternative therapy for treating severe depression.  A pilot study suggests that the anesthetic gas isoflurane commonly used during surgery could be used as an antidepressant. 

“The key finding from this study is that 75 percent of the patients treated with isoflurane improved their depression, and we saw no significant cognitive or memory side effects from the treatments,” says Howard Weeks, M.D., assistant professor of psychiatry and first author on a study published July 26, 2013, in PLOS ONE online.

Scores on the Quick Inventory of Depression Scale over 21 days of treatment, comparing electroconvulsive therapy (ECT) with isoflurane (ISO)
Scores on the Quick Inventory of Depression Scale over 21 days of treatment, comparing electroconvulsive therapy (ECT) with isoflurane (ISO)
Credit figure from the study published in PLOS ONE

Scientists don’t know for sure why the gas works, but they believe it basically shuts off electroactivity in the brain and allows it to reset. In this study, the success rate for isoflurane is similar to electroconvulsive therapy or ECT, but doesn’t have the same side effects. Weeks says many patients avoid ECT because it can be associated with cognitive impairments, including memory loss and attention problems.  And, he says, there is a stigma associated with it. For this reason, Weeks says millions of depressed people avoid treatment.

“So if we have a different treatment that doesn’t have the stigma that is just as effective and has less side effects, then that is going to open the door up for really changing how we treat depression,” Weeks says.

More research is needed however. Weeks says a much larger study treating hundreds of patients would be required before isoflurane could be proven effective.