A single intravenous dose of ketamine (0.5 mg/kg) rapidly reduced posttraumatic stress disorder (PTSD) symptom severity more than the active placebo midazolam in patients with chronic PTSD. Twenty-four hours after infusion, the ketamine group showed a mean reduction of 12.7 points on the Impact of Event Scale-Revised compared to midazolam. Ketamine also lessened comorbid depressive symptoms and improved overall clinical presentation. The treatment was generally well tolerated without persistent dissociative symptoms. These results suggest ketamine may offer a novel pharmacologic approach for chronic PTSD, though replication is needed.
A review of 88 articles examined how ketamine is given (oral, intravenous, intranasal, subcutaneous) for treatment-resistant depression and chronic pain. The methodological quality of studies on ketamine's antidepressant effects was low for all routes. Doses used for depression were lower than those for pain. Studies on pain suggest that oral ketamine may be acceptable for depression in terms of tolerability and side-effects, but few studies have systematically examined longer-term negative consequences. The authors conclude that rigorous randomized controlled trials are needed to study short- and longer-term depression outcomes and side-effects.