Comparison of the efficacy of topical 85% formic acid versus a combination of topical salicylic acid and lactic acid in the treatment of warts: A randomized, triple-blind, controlled trial

Background: Wart is a common skin disease that can occur at any age. While they are usually benign and self-limited, they can become irritating and cosmetically disabling to patients. The objective of this study is to compare the effectiveness of a topical 85% formic acid preparation with a combination of topical salicylic acid and lactic acid.Methods: We enrolled 66 patients, 7-60 years of age, in this triple-blind study. Patients were randomly divided into 2 groups: group 1 received a topical 85% formic acid solution and group 2 received DuoFilm (topical 16.7% salicylic acid + 16.7% lactic acid). The duration of treatment was a maximum of 4 weeks and we followed the patients every two weeks.Results: In group 1, 74.1% of the warts completely healed and 3.5% partially healed. In group 2 complete healing occurred in 40.8% and partial healing in 26.8% of the warts (P<0.001). Statistical analysis showed a significant difference in the favor of formic acid on the hands (P<0.001) but we did not observe a better effect for the feet. The time to complete healing was less for the majority of patients in the formic acid group (1 week versus 4 weeks). There were minimal adverse effects in each group, none that necessitated cessation of treatment.Conclusion: Topical formic acid had a higher cure rate for warts compared with a conventional preparation that consisted of both topical salicylic acid and lactic acid. This effect was particularly noted on the hands. This topical remedy could be regarded as an alternative to conventional treatments in the management of warts.