Because they appear in children more often than adults, flat warts are often referred to as juvenile warts. They usually develop in large clusters, containing anywhere from 20 to 200 warts.
Like other warts, these are caused by a contagious virus called the human papillomavirus (HPV).
Here, we discuss identifying flat warts and techniques for removing them, some of which can be done at home.
Identifying a flat wart
Flat warts are small, flat, and smooth. They generally form in clusters on the skin.
There are several characteristics of this type of wart. Flat warts:
- usually appear on a person's face, legs, or the backs of their hands
- are more common in children than adults
- may be yellow, brown, or pink
- are small and may be round or oval-shaped
- are about the size of the head of a pin
Flat warts commonly surround scratches or nicks on a person's skin. Men and women may notice them around shaving cuts on the face or legs.
Anyone concerned or unsure about a bump on the skin should consult a doctor. If a doctor cannot determine whether the lumps are flat warts on appearance alone they may wish to do a biopsy or make a referral to a dermatologist.
Treatment and removal
Flat warts usually do not require treatment and tend to disappear on their own. An estimated 23 percent of warts will disappear within 2 months, and up to 78 percent will disappear within 2 years.
Some people want to get rid of them sooner, and there are many useful treatments.
Over-the-counter treatments are available and a person can buy them online.
However, scientific research does not confirm the effectiveness of many wart-removal remedies. Consult a doctor before attempting home treatment.
A doctor can remove most types of warts. However, many of these removal techniques can cause warts to spread. Removal methods include:
- excision, which involves cutting or scraping away the wart with a scalpel
- burning, where the wart is removed using a laser
- cryotherapy, which involves freezing the wart with liquid nitrogen until it falls off
- applying cantharidin, a chemical that causes a blister to form under the wart and lift it from the skin
If the flat warts are on a person's face, hands, or another sensitive area, gentler treatments may be used to avoid scarring.
A doctor may instead prescribe a topical cream designed to irritate the skin so that the wart can be peeled away. These may include retinoic acid or benzoyl-peroxide creams.
The type of wart, a person's overall health and the size of the affected area can affect how long it takes for the lesions to disappear.
Consult a doctor before trying any home remedies for wart removal. Also, be aware that many home remedies are suggested for treating single warts, not clusters of flat warts.
A person should check with their pharmacist before taking any over-the-counter medication, and should always follow the instructions.
Apple cider vinegar is sometimes used to remove warts at home. However, this can cause chemical burns and scarring. Be very careful if attempting this home remedy.
Causes of flat warts
Flat warts can appear around shaving cuts.
The human papillomavirus (HPV) causes all types of warts. It has more than 100 different strains, and strains 3, 10, 28, and 49 can cause flat warts. These strains are benign, while other strains of HPV, such as those that affect the genitals, may increase the risk of developing cervical cancer.
A person is more likely to develop warts if they:
- have skin-to-skin contact with a person who has warts
- touch an object that has come into contact with a wart
- have cuts or scrapes
- practice poor hygiene
- have a weakened immune system, due to an illness or treatment such as chemotherapy, radiation therapy, or other medications
Around 7 to 10 percent of people are estimated to have non-genital strains of HPV, with many cases appearing between the ages of 12 and 16. Children and young people usually come into close contact more frequently than adults and are more likely to transfer the virus.
Wearing foot protection at public pools may help to prevent the spread of HPV.
Because HPV is highly contagious, people with warts should take steps to avoid spreading the virus.
They can do this by:
- refraining from rubbing, scratching, or picking at warts
- washing their hands after touching warts, even to apply a cream
- not sharing towels or other items that touch the skin
- keeping the skin clean and dry
- cleaning toys properly
Avoid contracting HPV by:
- refraining from touching another person's warts
- avoiding using the towels or other items of a person with the virus
- wearing flip-flops or shower shoes in public pools and locker rooms
While proper hygiene and the precautions above can help, a person may not be able to avoid contracting HPV.
Flat warts are likely to go away on their own and should not cause complications. However, some people seek treatment to eliminate them more quickly.
Warts may return and can spread to other parts of the body. People with warts can pass them on.
It a wart grows larger, bleeds, or changes color, contact a doctor.