Journal of

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Background and Aim: Common wart is a viral infection of epithelial tissues caused by human papiloma virus (HPV). In order to increase the efficacy and concurrent reduction of complications, different types of combination therapies have been recommended. One of them is the combination of cryotherapy with cantharidin. As cantharidin causes little pain and leaves small scars, we decided to design and conduct a randomized, controlled trial to investigate the efficacy of combined cryotherapy and topical cantharidin versus cryotherapy and a topical placebo. The mean number of the treatment sessions and complications of treatments were also compared between the two groups. Methods: This study was a randomized, controlled double blind clinical trial in which 110 patients with verruca vulgaris were randomly allocated into two groups. After cryotherapy in both groups, topical lotion of cantharidin 0.7% (Canthacur) and flexible collodion as placebo were applied topically in the intervention and control groups, respectively. Patients were followed for healing rates, complications and recurrence of the lesions. Results: The healing rates of lesions in both groups were 100%. The mean number of treatment sessions in the intervention and control groups were 3.4 and 4.7, respectively (P<0.001). The incidence of hyperpigmentation in the intervention and control group were 29.1% and 10.9%, respectively (P=0.017). Atrophic scars in the case group were less common than the control group (9.1% versus 29.1%). Within 4 weeks of follow up after completion of the treatment protocol, the frequency of other complications and recurrence of the lesions showed no statistically significant difference between the two groups. Conclusions: Combination of cryotherapy and cantharidin reduced the number of treatment sessions and atrophic scars, but increased the hyperpigmentation. Also, this combination therapy was ineffective in reducing other complications and the recurrence rate of the lesions.