Purpose: Although antidepressant drugs have been proven as an effective treatment for posttraumatic stress disorder (PTSD), there are few comparative studies of antidepressants that are acting on different neurotransmitters. The main aim of this study is to compare the efficacy of different class of antidepressant drugs on the PTSD. SUBJECTS/MATERIALS AND METHODS: In this open label study, the patients who met DSM-IV criteria for PTSD were randomly assigned to flexible doses of fluoxetine, moclobemide, or tianeptine. After the first assessment, consecutive assessments were performed at the end of weeks 2, 4, 8, and 12 using clinician administered PTSD scale (CAPS) and Clinical Global Impression of Severity (CGI-S). Changes in the total score of CAPS and sub-scale scores of symptom clusters (re-experience, avoidance, and hyperarousal) were the main output of efficacy. All statistics were based on intention-to-treat and last-observation-carried-forward (LOCF) principles.
Results: Thirty-eight patients were assigned to fluoxetine, 35 patients were assigned to moclobemide, and 30 patients were assigned to tianeptine group. Gender distributions and mean ages of the treatment groups were not significantly different. Drop-out rates due to an adverse events or unknown reasons were not significantly different among fluoxetine (18.4%), moclobemide (14.3%), and tianeptine (20.0%) groups. All three treatments has led to a significant improvement in PTSD severity assessed with CAPS total score (ANOVA P < 0.001). Similarly, total scores of re-experiencing, avoidance, and hyperarousal clusters that are subscales of CAPS were significantly reduced by all three treatments (with ANOVA all P values < 0.001). There was not significant difference in terms of treatment effect between three groups.
Discussion: Treatment groups showed very similar improvement on all ratings scales. The findings support that fluoxetine, moclobemide, and tianeptine are all effective in the treatment of PTSD. Different mechanisms of action for these antidepressant drugs might result in the same common neurochemical end point. However, further studies using different classes of antidepressant drugs are needed.