Lichen planus is a condition that causes purple or reddish-purple bumps that may be itchy to form on your skin. 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.
Lichen planus usually causes itching. The itching can be mild or very bad.
You may have just a few small bumps or you may have many. The bumps may persist for weeks or months, and may return once they go away. Sometimes, after the bumps go away, they leave a dark brown area on the skin. This is more likely to happen in persons of Asian, Hispanic or African heritage. These brown spots are not scars. They will slowly fade away, but it may take many months.
Lichen planus inside the mouth may cause painful sores that make it hard to eat.
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.
Only your doctor can tell if you have lichen planus. If you have any of the symptoms listed above, you should see your doctor. Your doctor may want you to have blood tests or a skin biopsy. For a biopsy, a small bit of skin is taken from one of the purple bumps. It is sent to a laboratory to see if it is lichen planus.
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 (one brand name: Benadryl).
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.
Light therapy (also called PUVA) can also be used in the treatment of lichen planus. Or, you could take a pill with a retinoid in it. Retinoids have many side effects. You have to have regular blood tests while you take this medicine.
Lichen planus of the scalp must be treated right away or the hair may never grow back.