Baclofen treatment for chronic posttraumatic stress disorder.

OBJECTIVE: Previous studies have shown the efficacy of gamma-aminobutyric acid B (GABA(B)) receptor agonists in treating anxiety in patients with panic disorder and in treating depression and anxiety in alcoholic patients. We hypothesized that baclofen, a GABA(B) agonist, would be an effective treatment in the symptomatic management of veterans with chronic posttraumatic stress disorder (PTSD).
METHODS: Fourteen male veterans with chronic, combat-related PTSD were enrolled in an open-label, 8-week, monotherapy trial of baclofen titrated to a maximum of 80 mg/d in 3 divided doses. The primary outcome measure was the Clinician-Administered PTSD Scale (CAPS), and secondary outcome measures included the Hamilton Rating Scale for Anxiety, the Hamilton Rating Scale for Depression, the Global Assessment of Functioning Scale, and the Clinical Global Impressions.
RESULTS: In the 11 patients who completed the 8-week trial, the mean total CAPS score decreased significantly from baseline (from 82.9 +/- 16.1 to 63.5 +/- 21.2). The avoidance and hyperarousal subscales showed significant decreases (from 36.2 +/- 6.2 to 26.5 +/- 9.6 and from 31.9 +/- 6.5 to 22.1 +/- 7.1, respectively), whereas the re-experiencing subscale remained unchanged. Significant improvements were also noted on all secondary outcome measures. Treatment response was noted within the first 4 weeks of treatment and was maintained throughout the trial. Baclofen therapy was well tolerated, as only 1 patient dropped out due to adverse effects.
CONCLUSIONS: Baclofen therapy was effective in treating both the PTSD symptoms and accompanying depression and anxiety in patients with chronic PTSD due to combat. Larger, double-blind, placebo-controlled studies are needed to confirm the efficacy of baclofen in the treatment of PTSD.