Ketamine to Treat Bipolar Depression

Bipolar depression and suicidal thoughts were improved after ketamine injection

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Ketamine is a drug commonly used in surgical anesthesia. A potential new use for this drug might be in the treatment of bipolar depression.

A recent study found that an injection of ketamine improved mood within minutes for people with bipolar disorder, who were not responsive to other medications.

The effects of the one-time injection lasted for up to two weeks.

"Ask your psychiatrist about available treatment options."

In an effort to replicate previous findings, Carlos Zarate, MD, of the National Institute of Mental Health, and colleagues enrolled 15 people with either type I or type II bipolar disorder.

All people in the study were not responsive to standard treatments, like lithium and valproate. They were given a ketamine injection and a placebo injection on two separate visits that were two weeks apart. Every participant received both the ketamine injection and the placebo, but the order of the treatments was random.

After the injection, the researchers measured depression symptoms using multiple standardized depression measures. Patients were assessed at 40, 80, 110 and 230 minutes after injection and again on days 1, 2, 3, 7, 10 and 14 after injection.

Depression symptoms decreased by the first 40 minute assessment when patients received a ketamine injection. The lower depression symptoms lasted for up to two weeks after the injection.

Ketamine also specifically reduced suicide ideation beginning at 40 minutes after injection, and the lower suicidal thoughts lasted until day three of the follow-up period.

Dr. Zarate and colleagues concluded that, “Taken together, these findings support the hypothesis that targeting the NMDA receptor complex brings about rapid antidepressant and antisuicidal effects in patients with bipolar depression.” 

“However, because the antidepressant effects of ketamine were not long lasting for most patients, it will be important to develop alternate strategies to sustain ketamine’s rapid antidepressant effects.”

More than 10 percent of the patients had discomfort within the first 40 minutes after injection, including feeling loopy, feeling woozy, nausea and headache, among others. However researchers report that all discomfort was gone by 80 minutes after injection.

Ketamine is a potent dissociative medication that can cause hallucinations, nightmares and euphoria, and it is sometimes abused for these effects. 

dailyRx spoke with Glen Elliott, MD, PhD, a clinical psychiatrist about the use of ketamine for these purposes. He said that he felt that, because ketamine is a serious drug with abuse potential, it is not likely to be used as a first-line treatment. Rather, it is most appropriate in acute and in-patient situations.

The study was published in the June issue of Biological Psychiatry. Dr. Zarate has applied for patent in conjunction with US government on ketamine for use in bipolar depression for which he will receive financial royalties.

Reviewed by: 
Review Date: 
June 7, 2012
Last Updated:
October 16, 2012