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

SUMMARY Objective: To evaluate the efficacy and tolerability of topiramate in patients with posttraumatic 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 São Paulo Hospital (Prove‐UNIFESP), São 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 anticonvulsants for the improvement of symptoms of PTSD.