The difference between Verrutop and other acid treatments is that it does not damage the surrounding skin. Another product available over-the-counter that can aid in wart removal is silver nitrate in the form of a caustic pencil, which is also available at drug stores. In a placebo-controlled study of 70 patients, silver nitrate given over nine days resulted in clearance of all warts in 43% and improvement in warts in 26% one month after treatment compared to 11% and 14%, respectively, in the placebo group. The instructions must be followed to minimize staining of skin and clothing. Occasionally, pigmented scars may develop. Procedures
Keratolysis, of dead surface skin cells usually using salicylic acid, blistering agents, immune system modifiers ("immunomodulators"), or formaldehyde, often with mechanical paring of the wart with a pumice stone, blade etc. Electrodesiccation
Cryosurgery or cryotherapy, which involves freezing the wart (generally with liquid nitrogen), creating a blister between the wart and epidermal layer after which the wart and the surrounding dead skin fall off. An average of 3 to 4 treatments are required for warts on thin skin. Warts on calloused skin like plantar warts might take dozens or more treatments. Surgical curettage of the wart
Laser treatment – often with a pulse dye laser or carbon dioxide (CO2) laser. Pulse dye lasers (wavelength 582 nm) work by selective absorption by blood cells (specifically hemoglobin). CO2 lasers work by selective absorption by water molecules. Pulse dye lasers are less destructive and more likely to heal without scarring.
But in 1874 it was noted by the dermatologist Ferdinand Ritter von Hebra that while various theories were advanced by the medical profession, the "influences causing warts are still very obscure".In 1907 the physician Giuseppe Ciuffo was the first to demonstrate that warts were caused by a virus infection. In 1976 the virologist Harald zur Hausen was the first to discover that warts were caused by the human papillomavirus (HPV). His continuous research established the evidence necessary to develop a HPV vaccine, which first became available in 2006. Other animals
References
External links

Wart photo library, Dermnet