Prazosin reduces nightmares in combat veterans with posttraumatic stress disorder

Preclinical and clinical observations suggest that the centrally active alpha1-adrenergic antagonist prazosin might alleviate trauma content nightmares and other symptoms in combat veterans with chronic posttraumatic stress disorder (PTSD).

In this retrospective chart review study, we analyzed data from 59 consecutive combat veterans with previously treatment-resistant chronic PTSD (DSM-IV criteria) and severe intractable trauma content nightmares to whom prazosin had been prescribed. Nightmare severity was quantified using the recurrent distressing dreams item of the Clinician Administered PTSD Scale (CAPS). Change in overall PTSD severity exclusive of nightmares was estimated by assigning a Clinical Global Impressions-Change scale (CGI-C) score based on chart review.

Mean +/- SEM recurrent distressing dreams item scores improved significantly (7.0 +/- 0.2 to 3.5 +/- 0.3, p <.0001) in the 36 patients who completed at least 8 weeks of prazosin treatment at their maximum titrated dose. The mean maximum prazosin dose achieved in these 36 patients was 9.6 +/- 0.9 mg/day. Recurrent distressing dreams scores also improved in the total group who filled their prazosin prescriptions (N = 51) (7.1 +/- 0.2 to 4.2 +/- 0.3, p <.0001). In a comparison group of 8 patients who did not fill their prazosin prescriptions but continued in outpatient treatment, there was no significant change in CAPS recurrent distressing dreams score (6.8 +/- 0.5 to 6.7 +/- 0.4). There also was at least some improvement in CGI-C ratings of overall PTSD severity exclusive of nightmares in a substantial majority of patients receiving prazosin, but not in the 8 comparison subjects. There were no serious adverse effects attributable to prazosin.

These observations suggest that prazosin may relieve symptomatic distress in PTSD, and they provide rationale for placebo-controlled trials of prazosin for PTSD trauma content nightmares and other PTSD symptoms.