274 Asadi N, Hemmati E, Namazi G, Pakniat Jahromi M, Sarraf Z, Pazyar N, et al. ijcbnm.sums.ac.ir Original article A Comparative Study of Potassium Hydroxide versus CO 2 Laser Vaporization in The Treatment of Female Genital Warts: A Controlled Clinical Trial Nasrin Asadi 1 , MD; Ensie Hemmati 2 , MD; Golnaz Namazi 2 , MD; Mahnaz Pakniat Jahromi 3 , MD; Zahra Sarraf 3 , MD; Nader Pazyar 4 , MD; Alireza Salehi 5 , MD, MPH, PhD 1 Maternal-fetal Medicine Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; 2 Department of Gynecology, Shiraz University of Medical Sciences, Shiraz, Iran; 3 Department of Gynecologic Oncology, Shiraz University of Medical Sciences, Shiraz, Iran; 4 Department of Dermatology, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 5 Research Center for Traditional Medicine and History of Medicine, Department of Epidemiology, Shiraz University of Medical Sciences, Shiraz, Iran Corresponding author: Ensie Hemmati, MD; Department of Gynecology, Shahid Faghihi Hospital, Zand Street, Shiraz, Iran Tel/Fax: +98 71 32332365; Email: drensie.hemmati@gmail.com Received: 4 August 2015 Revised: 7 September 2015 Accepted: 10 September 2015 abstract Background: Genital warts are the most common viral sexually transmitted disease affecting 1% of the population. A prospective, open-label controlled trial was performed to compare topical 5% potassium hydroxide (KOH) solution with CO 2 laser in the treatment of female genital warts. Methods: Seventy patients were enrolled in the study after convenience sampling. Right-sided lesions of the patients were treated by CO 2 laser every 3 weeks. The left-sided lesions of the same patients were treated by topical 5% KOH solution twice a day using a toothpick with cotton wrap on the tip. The patients were visited at 3, 6, and 9 weeks after initiation of the treatment and followed up for 6 months after the last visit. Results: Out of seventy patients, sixty three completed the study and were analyzed. A total of 56 KOH treated-patients (88.9%) showed complete response. On the other hand, 56 laser-treated patients (88.9%) presented complete clearing of the lesion. There was not any difference in response to both modalities of treatment. Complications of KOH solution and CO 2 laser were 24% and 19% respectively (P>0.05), but serious adverse events were not observed. The patients under KOH treatment displayed a recurrence rate of 11.1% (7 cases), while the same patients with CO 2 laser therapy demonstrated a recurrence rate of 7.9% (5 cases) (P=0.54). Conclusion: Topical 5% KOH solution was as effective as CO 2 laser in the treatment of female genital warts. There was not any serious complication in the application of KOH solution. This could be used as a new treatment for genital warts. Trial Registration Number: IRCT201412207848N1 KeywOrds: CO2 laser; Genital warts; Potassium hydroxide; Therapeutics Please cite this article as: Asadi N, Hemmati E, Namazi G, Pakniat Jahromi M, Sarraf Z, Pazyar N, Salehi AR. A Comparative Study of Potassium Hydroxide versus CO 2 Laser Vaporization in The Treatment of Female Genital Warts: A Controlled Clinical Trial. IJCBNM. 2016;4(3):274-282.