Formaldehyde 5% in flexible collodion compared to cryotherapy for treatment of female genital warts: A randomized clinical trial

Objectives: Genital wart is a sexually transmitted disease caused by human papillomavirus (HPV) and is responsible for discomfort, and decreased quality of life and productivity in victims with a high recurrence rate after treatments. This study aimed to compare the efficacy and safety of formaldehyde 5% with cryotherapy for the treatment of female genital warts. Methods: Eighty women with at least two similar genital warts who visited the outpatient dermatology clinic of Shahid Faghihi hospital, Shiraz, Iran, were enrolled in this study. One lesion of each patient was self-treated with formaldehyde 5% in flexible collodion gel once daily for 28 days and the other matched lesion was treated by weekly repeated cryotherapy courses. The number of eradicated lesions and the mean days needed to treat, pain scores, complications and patient satisfaction were compared between the treatment methods. Results: Complete clearance of lesions was observed in 58.7% of formaldehyde-treated lesions compared to 88.7% for cryotherapy (P value = 0.000). With formaldehyde-treated lesions, 51% complained of pain, 36.3% had pruritus, 86.3% had skin dryness, 88.8% complained of burning sensation and 93.7% showed erythema. In the cryotherapy group, 92.5% complained of pain, 15% had burning sensation, 75% showed erythema, 5% had atrophy, 80% developed post-inflammatory hyper or hypopigmentation (PIH) and 92.5% suffered from ulceration. Seventy-five (93%) found it easy to apply and (47) 58% were satisfied with their treatment results. Conclusions: Self-administration of formaldehyde 5% resulted in a lower clearance rate but had better cosmetic outcomes with lower pain scores compared to cryotherapy.