What is lichen planus?
Lichen planus is a skin condition that causes purple or reddish-purple bumps that may be itchy. The bumps have flat tops and are uneven in shape. If you look at the bumps closely, you might see white scales or flakes on them.

Lichen planus commonly affects the inner wrists, the forearms and the ankles. It may also affect the scalp, the nails, the inside of the mouth, the genitals and the anus. On the scalp, lichen planus may cause hair loss. Lichen planus of the nails can cause brittle or split nails. In the mouth, it looks like lacy white patches on the inside of the cheeks or on the tongue. Lichen planus of the mouth, genitals or anus can cause soreness and a burning sensation. Sometimes lichen planus affects areas of skin where you had a cut or burn.

Men and women can get lichen planus. It may affect people of any age, but it is more common in middle-aged adults.

What causes lichen planus?
In many cases, the cause of lichen planus can't be found. It is not contagious. You can't "catch" it from or "give" it to someone else. It is not caused by stress, but sometimes stress makes it worse.

Some cases may be linked to a virus called hepatitis C. This virus can cause liver disease. Your doctor may want to order a blood test to check for hepatitis C virus. Some medicines can cause lichen planus. It is important to tell your doctor about all the medicines you are taking.

How is lichen planus treated?
There is no cure for lichen planus, but medicine can relieve the itching and help the rash get better. If your itching is very bad, your doctor may suggest an antihistamine.

Most of the time, the bumps caused by lichen planus go away without any treatment after about a year. If your lichen planus is severe or if you have many bumps, your doctor may prescribe corticosteroid pills.

Corticosteroid gels and ointments are used to treat lichen planus of the genitals or anus and lichen planus of the mouth if symptoms are severe. If you have lichen planus of the mouth and your symptoms are mild, you may not need any treatment. Or your doctor may recommend a mouth rinse to relieve any discomfort caused by mouth sores.

Corticosteroids have many side effects, so be sure to follow your doctor’s instructions carefully when taking these medicines.

Lichen planus of the scalp must be treated right away or the hair may never grow back.