Pilot study of secondary prevention of posttraumatic stress disorder with propranolol

Background: Preclinical considerations suggest that treatment with a β-adrenergic blocker following an acute psychologically traumatic event may reduce subsequent posttraumatic stress disorder (PTSD) symptoms. This pilot study addressed this hypothesis. Methods: Patients were randomized to begin, within 6 hours of the event, a 10-day course of double-blind propranolol (n = 18) versus placebo (n = 23) 40 mg four times daily. Results: The mean (SD) 1-month Clinician-Administered PTSD Scale (CAPS) score of 11 propranolol completers was 27.6 (15.7), with one outlier 5.2 SDs above the others’ mean, and of 20 placebo completers, 35.5 (21.5), t = 1.1, df = 29, p = .15. Two propranolol patients’ scores fell above, and nine below, the placebo group’s median, p = .03 (sign test). Zero of eight propranolol, but six of 14 placebo, patients were physiologic responders during script-driven imagery of the traumatic event when tested 3 months afterward, p = .04 (all p values one-tailed). Conclusions: These pilot results suggest that acute, posttrauma propranolol may have a preventive effect on subsequent PTSD.