Ketamine Significantly Improves PTSD Symptoms

April 22, 2014

Twenty-four hours after receiving a single infusion of IV-administered ketamine, the severity of post-traumatic stress disorder (PTSD) symptoms in patients with chronic PTSD was significantly reduced compared to active placebo, according to a study published in the online JAMA Psychiatry. 

“These findings may lead to novel approaches in the treatment of chronic PTSD—a condition that affects a broad spectrum of adults in the United States and beyond, including victims of sexual assault, war veterans, those who have witnessed catastrophic events such as the September 11 terror attacks, and others,” said lead author Adriana Feder, MD, associate professor of psychiatry at the Icahn School of Medicine at Mount Sinai, New York City. 

“However, this should be viewed as a proof-of-concept study. Additionally, longer term clinical trials with ketamine will be required to determine if ketamine will be a clinically useful treatment for PTSD.” 

In the double-blind, crossover study, researchers randomly assigned 41 adults with chronic PTSD and free of concomitant psychotropic medications to receive a single 40-minute IV infusion of ketamine hydrochloride or midazolam, an active placebo chosen for its similar pharmacokinetic parameters and nonspecific behavioral effects. Two weeks later, the patients received a single IV infusion of the remaining medication. 

Before and at several points after each infusion, researchers assessed participants’ PTSD symptoms using the Impact of Event Scale-Revised (IES-R). They found that compared with midazolam, ketamine was associated with a significant improvement in IES-R scores 24 hours after infusion. In seven patients who received ketamine first, researchers found significant improvement at two weeks post-infusion; just one patient who received midazolam first experienced a similarly sustained benefit. 

In addition, ketamine was associated with reduced depressive symptoms and an improved clinical presentation overall, researchers reported. The drug, they added, was well-tolerated in study participants. 

 —Jolynn Tumolo 


1. Feder A, Parides MK, Murrough JW. Efficacy of intravenous ketamine for treatment of chronic posttraumatic stress disorder: a randomized clinical trial. JAMA Psychiatry. 2014 April 16. [Epub ahead of print]. 

2. Intravenously administered ketamine shown to reduce symptoms of chronic post-traumatic stress disorder [press release]. Newswise: Charlottesville, VA; April 16, 2014.

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