May 21, 2015 | Louise Gagnon
"It is a medication that is used to treat conditions like high blood pressure and benign prostatic hypertrophy," explained Davit Khachatryan, MD, MHSC, Queen's University, Kingston, Ontario, Canada, on May 16. "There has been a reaction in terms of decreasing startle response, which is a key feature of PTSD. It is a medication that suppresses the noradrenergic stimulation, and in doing that, it suppresses the startle response."
The medication is prescribed off-label to reduce sleep disturbance, nightmares, and flashbacks, which are core symptoms of PTSD.
"There is a lack of formal evidence [with respect to prazosin use], which is why it is not considered a first-line therapy in treatment guidelines," said Dr. Khachatryan.
Dr. Khachatryan and colleagues conducted a comprehensive search using various databases. They identified 246 articles and included 6 randomised, double-blind, placebo-controlled trials that had durations of between 7 and 20 weeks. Patients included veterans, civilians, military on active duty, and a mix of populations, aged 30 to 56 years. The mean dose range of prazosin in the studies was 3.1 to 15.6 mg/day.
The researchers used a random-effect model to calculate effect sizes, which were computed as Hedges' g. They found that prazosin was superior to placebo in improving sleep quality (g = 0.987), reducing overall PTSD symptoms (g = 0.699), and decreasing sleep disturbances in particular (g = 0.799).
"These findings support the use of prazosin to treat sleep disturbances in PTSD," concluded Dr. Khachatryan, noting that his team will continue to pool data from accumulating experience of prazosin use to treat sleep disturbance linked to PTSD.
[Presentation Title: Prazosin in the Treatment of Nightmares in PTSD: Systematic Review and Meta-Analysis. Abstract P2-117]