This double-blind controlled clinical trial will recruit 60 patients with verruca vulgaris -with minimum of one lesion that has minimum diameter of 6 millimeter- who visit the dermatology clinic of Afzalipour Hospital (kerman, Iran).
Exclusion criteria are lesions on face, genitalia and periungual; patients under 12 and above 50 years; immune suppression; pregnancy and lactating; patients who has received any treatment.
Table of random numbers will be used for random allocation of the patients.
Both groups will receive cryotherapy with liquid nitrogen (with the usage of cotton swabs and double freez-thaw cycle until creating two-millimeter white halo around lesions) every other week .
Patients in group A and B will receive 2% niosomal zinc sulfate cream and placebo twice a day, respectively.
Treatment will be performed for maximum 3 months or until total clearance of the lesions, whichever occurs first.
The patients will be included if diagnosis is confirmed by careful clinical examination.
A demographic questionnaire and consent form will be filled out at baseline.
A researcher unaware of grouping will visit at baseline and after 2, 4, 6, 8,10 and 12 weeks.
Every other week patients in both groups will be visited by researcher to observe side effects (hyperpigmentation, hypopigmentation, blister, pruritus) and lesion's response to treatment (complete lesion disappearance, size reduction).
Two and four weeks after clearance of lesions patients will be examined for any possible recurrence.