AbstractOBJECTIVES: To evaluate the long-term remission efficacy and safety of isotretinoin in the treatment of Behcet's disease (BD). PATIENTS and METHODS: This single-blind, controlled therapeutic study was conducted in the Department of Dermatology and Venereology at Baghdad Teaching Hospital from February 2011 to January 2012. Thirty patients with BD were included in this work. Each patient received isotretinoin 20 mg orally once daily for 3 months. They were assessed at week 2 and then monthly depending on the Clinical Manifestation Index (CMI) and to record any side effects. At week 12, isotretinoin was stopped and patients were given placebo therapy in a form of glucose capsules for another 3 months. RESULTS: Thirty patients were treated, 14 (46.6%) males and 16 (53.3%) females, with a male to female ratio of 1:1. Their ages ranged from 16 to 64 years (mean +/- standard deviation [SD], 38.4 +/- 10.9 years). During the first 3 months of therapy, the pathergy test, oral pathergy test, and C-reactive protein were significantly minimized. The CMI before isotretinoin therapy ranged between 2 and 8 (mean +/- SD, 4.933 +/- 1.91). After therapy, within the first 14 days, the mean CMI started to decline to a lower level, and it continued to decline significantly until week 12. It then started to increase through week 4 of placebo therapy, but remained statistically significant until the second month of placebo therapy. Isotretinoin therapy also had a statistically significant effect in reducing oral ulcers and skin manifestations. CONCLUSION: Isotretinoin is an effective therapeutic and prophylactic drug in the management of BD. J Drugs Dermatol. 2013;12(4):e68-e73.