Placebo-Controlled, Triple-Blind, Randomized Crossover Pilot Study of the Safety and Efficacy of Four Different Potencies of Smoked Marijuana in 76 Veterans with Chronic, Treatment-Resistant Posttraumatic Stress Disorder (PTSD)
This study was the first randomized placebo-controlled trial of smoked cannabis for posttraumatic stress disorder (PTSD) which explored whether three different concentrations of smoked marijuana could help reduce PTSD symptoms in 76 U.S. veterans with chronic, treatment-resistant PTSD. Participants were U.S. veterans, aged 18 or older with a diagnosis of PTSD that did not improve after trying either medication or psychotherapy.
The study used a double-blind, cross-over design, where participants were randomly assigned to receive three weeks of either active treatment or placebo and then were re-randomized after a 2-week washout period to receive one of the other three active treatments in Stage 2. The treatments consisted of High THC (approximately 12% THC and < 0.05% CBD), High CBD (11% CBD and 0.50% THC), THC+CBD (approximately 7.9% THC and 8.1% CBD), and placebo (< 0.03% THC and < 0.01% CBD).
All treatment groups, including placebo, showed good tolerability and significant improvements in PTSD symptoms during three weeks of treatment. However, no active treatment with cannabis outperformed placebo.
- Current Status: Completed
- ClinicalTrials.gov Record
- Study Protocol
- PRESS RELEASE: Statement on the Adequacy of Marijuana Provided by NIDA for Phase 2 Clinical Trials for PTSD in Veterans (March 17, 2017)
- PRESS RELEASE: First Clinical Trial of Marijuana for PTSD in Veterans Nearly Completes Enrollment (August 9, 2018)