Recent studies have shown the role of sorotonergic system in posttraumatic stress disorder. Terazodone and Nefazodone, (5HT2 antagonist) ameliorated PTSD nightmares but the reports are mixed. This study prompted an open trial of cyprohepatadine for Iran versus Iraq combat PTSD patient nightmares.

25 patients studied in an eight - week, Before - After trial of cyproheptadine, the participants were male and chronic PTSD patients with combat related nightmare the exclusion criteria in clouded current substance abuse or dependence, psychotic disorder and any medical condition that contraindicated the use of cyproheptadine.

Five patients were excluded from the study because of side effects including dizziness and somnolence. Twenty patients completed the study. Average of nightmare severity decreased from 6.85 to 5.05, which was statistically significant (P<0.01).

Cyproheptadine, 5HT2 antagonist may be effective in PTSD nightmare treatment.