A Double-Blind Randomized Controlled Trial To Study the Efficacy of Topiramate in a Civilian Sample of PTSD

Objective: To evaluate the efficacy and tolerability of topiramate in patients with post-traumatic stress disorder (PTSD). Method: We conducted a 12-week double-blind, randomized, placebo-controlled study comparing topiramate to placebo. Men and women aged 18-62 years with diagnosis of PTSD according to DSM-IV were recruited from the outpatient clinic of the violence program of Federal University of Sao Paulo Hospital (Prove-UNIFESP), Sao Paulo City, between April 2006 and December 2009. Subjects were assessed for the Clinician-Administered Posttraumatic Stress Scale (CAPS), Clinical Global Impression, and Beck Depression Inventory (BDI). After 1-week period of washout, 35 patients were randomized to either group. The primary outcome measure was the CAPS total score changes from baseline to the endpoint. Results: 82.35% of patients in the topiramate group exhibited improvements in PTSD symptoms. The efficacy analysis demonstrated that patients in the topiramate group exhibited significant improvements in reexperiencing symptoms: flashbacks, intrusive memories, and nightmares of the trauma (CAPS-B; P = 0.04) and in avoidance/numbing symptoms associated with the trauma, social isolation, and emotional numbing (CAPS-C; P = 0.0001). Furthermore, the experimental group demonstrated a significant difference in decrease in CAPS total score (topiramate -57.78; placebo -32.41; P = 0.0076). Mean topiramate dose was 102.94 mg/d. Topiramate was generally well tolerated. Conclusion: Topiramate was effective in improving reexperiencing and avoidance/numbing symptom clusters in patients with PTSD. This study supports the use of anti-convulsants for the improvement of symptoms of PTSD.