A Placebo-Controlled Trial of Guanfacine for the Treatment of Post Traumatic Stress Disorder in Veterans

Preclinical and clinical studies demonstrate a hyperactivity of the norepinephrine system in patients with posttraumatic stress disorder (PTSD). α-2 adrenergic agonists have been shown to ameliorate symptoms of PTSD, likely because of their ability to dampen noradrenergic tone. This study tests the ability of the α-2 adrenergic agonist, guanfacine, to reduce the symptoms of PTSD. Experimental Design: Patients with chronic PTSD were randomized (1:1) to an 8-week double-blind, placebo-controlled treatment of guanfacine followed by a 2-month, open-label extension phase. Patients were maintained on their stable doses of allowed antidepressants during the trial. Efficacy was measured by the following assessment scales: Clinician Administered PTSD Scale (CAPS), Montgomery Asberg Depression Rating Scale (MADRS), Clinical Global Impression-Severity (CGI-S), Clinical Global Impression-Improvement (CGI-I), and Davidson Trauma Scale (DTS, self-report). Principal Observations: There were no significant differences in the drug versus placebo responses for the clinician-administered or patient self-report outcome measures in this small sample of predominantly male combat veterans with PTSD. However, the medication was well tolerated. Conclusion: Similar to previous findings, this small pilot study failed to show differences in the response to guanfacine versus placebo in a small sample of predominantly male combat veterans with PTSD.