Efficacy and Safety of Topical Cantharidin Treatment for Molluscum Contagiosum and Warts: A Systematic Review

Background and Objective: Topical cantharidin is routinely used for the treatment of molluscum contagiosum and warts. The objective of this systematic review is to assess the efficacy and safety of topical cantharidin treatment for molluscum contagiosum and warts. Methods: We performed a systematic review of studies assessing topical cantharidin treatment of molluscum contagiosum or warts. We searched the databases of Cochrane, EMBASE, GREAT, LILACS, MEDLINE, and Scopus. Two authors performed the study selection and data extraction. Results: Twenty studies (1958–2018) met inclusion/exclusion criteria. Twelve studies assessed warts, and eight studies assessed molluscum contagiosum. Overall, 1752 patients were included (range 0.3–62 years; specified in 15 studies). Clearance rates with topical cantharidin for molluscum contagiosum were variable (range 15.4–100%). Significant clearance of warts with maintenance of clearance was demonstrated with topical cantharidin alone. Topical cantharidin in combination with podophyllotoxin and salicylic acid demonstrated efficacy for plantar warts (pediatric and adult; clearance rate range 81–100%; four studies had 100% clearance), with the majority clearing after a single treatment. Satisfaction with cantharidin therapy was high, especially in molluscum contagiosum. Pain (7–85.7%), blistering (10–100%), and hyper-/hypopigmentation (1.8–53.3%) were the most commonly occurring adverse effects with cantharidin treatment. Conclusion: Topical cantharidin demonstrated clearance of warts, particularly in combination with podophyllotixin and salicylic acid, and modest benefit for pediatric molluscum contagiosum with good tolerability and safety.