Warts (Verruca)

Warts, or verrucae (singular: verruca), are benign growths on the skin or mucous membranes that cause cosmetic problems as well as pain and discomfort. They are seen on people of all ages but most commonly appear in children and teenagers.


Jennifer J. Janiga, MD, FAAD -- Warts (Verruca)

Warts (Verruca)


What are warts?

Warts, or verrucae (singular: verruca), are benign growths on the skin or mucous membranes that cause cosmetic problems as well as pain and discomfort. They are seen on people of all ages but most commonly appear in children and teenagers. The incubation period of a wart is from 2 to 9 months following infection with the human papilloma virus (HPV); during which time an excessive proliferation of skin growth slowly develop. More than 50% of them disappear on their own within two years.

What causes warts?

Warts are caused when a virus infects the skin. It is contagious and usually comes from direct skin to skin contact. The virus that causes warts is the Human Papilloma Virus. More than 80 different types of HPV have been identified.  Most have an affinity for the skin and produce common warts (verruca vulgaris), flat warts (verruca plana), and plantar or foot warts (verruca plantaris). Several other types of HPV have an affinity for mucous membranes and some of these cause genital warts (condyloma acuminate). HPV is passed from person to person by direct or indirect contact and from one body location to another on the same person. The virus more easily enters the body through an area of skin that is moist, peeling, or cracked. Some types (e.g., condyloma acuminta) are transmitted sexually. The degree of contact, location, the amount of virus present (newer warts tend to contain more viral particles than older warts), and the person’s immunity are the factors that determine how severe the infection.

What are the signs and symptoms of warts?

Common warts appear most often on the tops of the fingers and hands, usually along the cuticles, as rough, thick cauliflower-like papules that develop solitarily or in large numbers. Black dots, which are minute blood vessels, can be seen in them. Small warts may surround the original lesion because the virus is usually present in a one-to-two millimeter radius surrounding the original wart. Flat warts are small, slightly elevated, flat-topped, and pink or tan papules, are smoother than the common wart, and have minimal scale. They occur primarily on the face, arms, and legs, and a person can have several, even hundreds of them. Plantar warts occur on the soles of feet, they are often thick and callused, grow inward, and can be quite painful and bothersome. Tiny clusters of warts, called mosaic warts, are particularly stubborn and resistant to treatment. Ano-genital warts (condyloma acuminata) are flesh to gray in color, grow in mucous membranes, and vary in size from small, shiny papules, to large cauliflower-like lesion They can extend internally into the vagina and cervix, the rectal area, and inside the urethra (the tube through which urine is voided from the bladder). Most of these warts are painless, but there can be itching and burning and they can progress to more serious disease, regress, or remain at their primary growth stage.

How are warts diagnosed?

The diagnosis is most often made on the basis of clinical appearance. Diagnostic clues include black dots within the warts and/or pinpoint bleeding after removing down the thickened skin. The wart also tends to disturb the natural skin lines and creates a disrupted surface. A biopsy can be used to confirm clinical suspicion if necessary.

How are warts treated?

Dr. Jennifer Janiga uses various effective treatments for warts; management is based on the age of the individual as well as the size, number, and location of warts. Common warts, especially in children, do not necessarily need to be treated, because they exhibit a high rate of spontaneous remission. Without treatment, however, spread can occur.

Treatment involves the physical or chemical destruction of the lesion. In physical destruction, liquid nitrogen, which is extremely cold, is sprayed onto the wart or applied by a cotton tipped swab. Because freezing is painful, this form of treatment is not tolerated well by young children. Warts can be anesthetized and then scraped with a curette, burned (desiccated), removed by laser, or surgically cut out (excised).

A variety of chemicals are used to eradicate warts. Genital warts may respond to a topical resin, ponophyllin, applied in strong concentration at regular intervals by Dr. Janiga, or a prescription gel (Condylox®) to be used at home. Cantharidin, an extract of a blistering beetle, is used alone or in combination with podopyllin to treat warts.

Over-the-counter preparations of salicylic acid are sometimes used. Imiquimod cream (Aldara®) is approved as a prescription for enhancing the immune response to warts, thus helping the body fight the human papilloma virus. This cream is FDA approved for genital warts.  Despite numerous treatment modalities, warts usually require repeated treatments because they are difficult to eradicate and commonly recur.

Can warts be prevented?

Treating warts while they are still small may prevent them from spreading. The most effective way to prevent ano-genital warts (condyloma acuminata) is to use a condom during sex and to avoid contact with affected individuals.

For more information, or to set up a consultation with Dr. Jennifer Janiga to discuss evaluation of and treatment for warts in our Reno / Tahoe dermatology and plastic surgery office, please send us an email or call 775-398-4600. Appointment length varies but is usually not more than 15-30 minutes.


Jennifer J. Janiga, MD, FAAD

Dr. Janiga enjoys taking care of both adults and children. Her extensive training and years of experience in medical dermatology, lasers, and cosmetic procedures allows her to treat her patients with the comprehensive attention they deserve.

Dr. Janiga listens attentively to what patients have to say, and works with them in planning the right course of action on an individual basis. Honest talk, humility and a fresh perspective paired with years of experience and education all contribute to the effectiveness of her straightforward care.