Clinical Question: Is freezing more effective than salicylic acid treatment of plantar warts?

Bottom Line: Cryotherapy with liquid nitrogen was no more effective than daily treatment with salicylic acid to remove plantar warts (verrucae) from patients aged at least 12 years. The success rates in both groups were low, with only approximately one third of patients experiencing total clearance. (Level of Evidence: 1b)

Reference: Cockayne S, Hewitt C, Hicks K, et al, on behalf of the EVerT Team. Cryotherapy versus salicylic acid for the treatment of plantar warts (verrucae): a randomised controlled trial. BMJ 2011;342:d3271.

Study Design: Randomized controlled trial (double-blinded)

Funding Source: Government

Allocation: Concealed

Setting: Outpatient (any)

Synopsis: This study compared repeat cryotherapy with daily salicylic acid keratolysis in the treatment of 240 patients aged at least 12 years who had at least one wart deemed suitable for treatment with either approach. The patients were assigned, using concealed allocation, to up to 4 cryotherapy treatments (average = 1.6) by a physician or to daily self-treatment with pumicing of dead skin followed by the application of 50% salicylic acid for up to 8 weeks. Although the investigators were expecting success rates to be in the 70% to 80% range, results in both groups were much lower: At 12 weeks, complete clearance occurred in 14% in both groups. At 6 months the difference was 31% vs 34%. In the United States, the maximum strength of nonprescription salicylic acid is 40%. Patient satisfaction scores were higher with cryotherapy.