Common wart (verruca vulgaris)
Mainly on the hands and feet, sometimes on the knees and elbows. Often cauliflower-like bumps that can feel hard. There are usually several at once.
Infection
Medically reviewed by Dr. A.M. van Coevorden, dermatologist
± 5 min read
Wartsrough bumps caused by a virus
Warts are rough, often cauliflower-like growths of the skin, caused by the human papillomavirus. The medical name is verruca. They mainly appear on the hands and feet, but can occur anywhere on the body, and there are often several at once. Warts are common, especially in children and young adults.
How do you get warts?
Warts are caused by a virus, the human papillomavirus. This virus is contagious. You can get a wart when your skin comes into contact with the virus. This happens more easily when the skin is broken or softened. The time between infection and the appearance of a wart varies: usually two to six months, but it can also take longer than a year.
What types of wart are there and what do they look like?
Most of the time warts do not bother you, but some can be painful. Many people do not like the look of a wart. Warts are classified by where they appear or by their shape.
The main forms:
Plantar wart (verruca plantaris)
On the sole of the foot, often with a thick layer of callus on top. There are two kinds: the mosaic wart, which spreads superficially, and the myrmecia wart, which grows deep and is painful. Plantar warts are often stubborn and grow deep because of the pressure on the sole.
Flat wart (verruca plana)
A smooth, flat bump a few millimetres across, skin-coloured, pink or light brown. There are often many at once, especially on the face, forearms, backs of the hands and legs.
Filiform wart (verruca filiformis)
A small protrusion of the skin on a narrow stalk, usually on the face. In children mainly on the lips, nose or eyelids.
Are warts contagious?
Y
Yes. Warts are contagious. You get them through contact with someone who has warts. Plantar warts are probably picked up from infected skin flakes and bits of wart, for example by walking barefoot in changing rooms, showers, swimming pools and gyms.
How does your doctor diagnose warts?
Your doctor can usually tell straight away whether you have warts. Sometimes some of the hardened skin is scraped away, which reveals the characteristic black dots.
What treatments are available?
Treatment is often not needed. In two thirds of people the warts disappear on their own within two years. Treatment is only needed if they bother you, hurt or trouble you cosmetically. The aim of every treatment is to destroy the top layer of skin, where the virus particles are.
Treating warts is not straightforward. There is no single method that works for everyone, and the results are variable and often disappointing.
The different treatments:
Salicylic acid (paint-on liquid or ointment)
Proven effective. It softens the horny layer. Apply it once a day; it works better under a plaster. Protect the surrounding skin with petroleum jelly and regularly remove the softened layer with a blade, callus file or pumice stone, after first soaking the wart in warm water for a quarter of an hour. Continue for one to two weeks after it has gone. The treatment can be painful and sometimes irritating.
Freezing with liquid nitrogen
The wart is frozen, forming a blister with the wart in the blister roof. The skin heals within four to seven days. It often has to be repeated after a few weeks. It is less successful for plantar warts because the horny layer there is thicker. The treatment is painful, can cause blood blisters, and around the nails it can damage the nail permanently.
Tri-, bi- or monochloroacetic acid
Aggressive, caustic substances for thick warts on the palms and soles. They are applied every seven to ten days, with salicylic acid in between to soften the wart further.
Curettage or excision
Under local anaesthetic the wart is scooped or cut out and the wound is cauterised. The wound heals in about two weeks. In 20% the wart returns within a few months, and there is a risk of permanent scarring. Plantar warts are therefore preferably not cut out.
Vitamin A acid cream
Thins the horny layer and works mainly on flat warts. Apply once or twice a day. Sun protection is important, because this product makes the skin more sensitive to sunlight.
Laser therapy and others
Laser therapy can sometimes help with plantar warts. For stubborn warts, bleomycin can be injected into the wart. For duct tape, diphencyprone, 5-fluorouracil, photodynamic therapy and interferon the effectiveness has not been proven.
Warts under the nail are very difficult to treat. Sometimes the nail is removed to reach the wart better, but freezing around the nail can damage it permanently.
Can warts be cured?
Most warts disappear on their own, but it can take a long time. Warts on the hand, under the nails and on the soles can be very stubborn. They also often come back, sometimes in a different place from where they first were.
What can you do yourself?
- Do not walk barefoot in shared spaces such as swimming pools and gyms. Prevention is only really useful for plantar warts.
- For after-pain following treatment, use a painkiller such as paracetamol.
- When several large plantar warts are treated at the same time, bring someone who can take you home.
Frequently asked questions about warts
Are warts contagious?
Yes. You get them through contact with someone who has warts, or via infected skin flakes. Plantar warts are often picked up by walking barefoot in changing rooms, showers and swimming pools.
Do warts need to be treated?
Usually not. In two thirds of people they disappear on their own within two years. Treatment is only needed if they bother you, hurt or trouble you cosmetically.
How long before a wart appears?
The time between infection and the first wart varies: usually two to six months, but it can also take longer than a year.
Why do my warts keep coming back?
Warts on the hand, under the nails and on the soles are stubborn and often come back, sometimes in a different place. Treatment does not work equally well for everyone.
Can I treat warts myself?
A paint-on liquid or ointment with salicylic acid is proven effective and available without a prescription. Soak the wart in warm water first, protect the surrounding skin with petroleum jelly and regularly scrape away the softened layer.
Sources and more information
Source: Dutch Society of Dermatology and Venereology (NVDV).
Related skin conditions
All conditions A–ZMolluscum contagiosum
Small, shiny bumps caused by a virus, especially in children.
Seborrhoeic keratosis
Benign, wart-like spots that appear with age.
Corns
Painful patches of hard skin from pressure or friction, not a virus.