For millions of people living with post-traumatic stress disorder (PTSD), nightfall often brings distressing nightmares instead of restful sleep. However, a new clinical trial suggests that an active compound found in cannabis could offer significant relief.
Researchers in Germany discovered that dronabinol, a purified oil containing tetrahydrocannabinol (THC)—the main psychoactive component in cannabis—more than doubled the likelihood of completely eliminating nightmares in PTSD patients compared to a placebo.
The trial, led by Dr. Stefan Röpke at Charité–Universitätsmedizin Berlin, included 171 participants with PTSD who suffered from frequent and severe nightmares. Over a 10-week period, 87 participants took a nightly dose of dronabinol one hour before sleep, gradually increasing from 2.5 milligrams up to a maximum of 15 milligrams until nightmares stopped. The remaining 84 participants received a placebo.
By the end of the study, participants taking dronabinol reported a 3.7-point reduction on an 8-point nightmare severity scale, showing 1.5 points more improvement than the placebo group. Furthermore, 58 percent of the dronabinol group experienced at least a 50 percent reduction in nightmare frequency and intensity, and 37 percent saw their nightmares disappear completely.
Scientists suspect THC may work by interacting with the brain's endocannabinoid system, which helps regulate sleep, or by reducing rapid eye movement (REM) sleep, the stage where vivid dreams primarily take place.
Despite the promising findings, experts urge caution. Dr. Carrie Cuttler from Washington State University warned that stopping THC treatment suddenly can trigger a rebound effect, causing intense nightmares to return and potentially leading to cannabis dependence. Dr. Röpke also stressed that individuals should not self-medicate and that any THC-based treatment must be prescribed and monitored by a qualified physician.