Lichen planus is an inflammatory skin condition. It appears as rows of itchy, flat-topped bumps (lesions) on the arms and legs. Sometimes, lichen planus affects the mucous membranes, especially in the mouth and genitals, causing pain, soreness or a burning sensation. Lichen planus isn’t an infectious disease and isn’t contagious. But it can be persistent, lasting months or even years. It may later reappear. This makes treatment of lichen planus difficult. Self-care measures, such as tub soaks and cool compresses, can help. But more-bothersome symptoms may need prescription ointments or creams to reduce the itching and inflammation. Anyone, of any race or age, can develop lichen planus. However, lichen planus is most common in middle-aged adults and occurs more often in women. Also, if you have liver disease, such as hepatitis C viral infection or scarring of the liver (cirrhosis), you’re more likely to develop lichen planus.
Lichen planus is an itchy rash, usually on the insides of the wrists, ankles and forearms. This rash can also appear on the scalp, lower back, neck, nails, and mucous membranes that line the mouth, nose, vagina, penis and anus. Lichen planus may cause scarring when it involves the nails or scalp.
Signs and symptoms of lichen planus include:
- Rows of flat-topped bumps that may vary in color from purple to pink to red
- Itching, which may be severe
- Soreness or a burning sensation when involving the mucous membranes
- Grooving, splitting, thinning or nail loss when involving the nails
- Redness, irritation, hair thinning and hair loss when involving the scalp
The initial attack may persist for weeks or months, and recurrences can continue over many years. Once the rash resolves, dark brown or gray spots may linger on the skin. These may be more noticeable if you have darker skin.
Signs and symptoms of oral lichen planus include:
Oral lichen planus — lichen planus of the mouth — may appear before the skin rash and be the only evidence of the disease.
- Small, pale raised areas or bumps that form a lacy network on the tongue or inside the cheeks
- Shiny, red, slightly raised patches on the tongue or cheeks
- Red, open sores in the mouth
- Pain, tenderness, burning or itching in the mouth
- Dry mouth
- A metallic taste or a blunted taste sensation
The exact cause of lichen planus isn’t known. In some cases, it appears to be triggered by an allergic or immune reaction to a medication or other substance. And some cases have been linked to infections, such as hepatitis C. But more often, the source can’t be determined.
Lichen planus of the skin is generally noncancerous (benign). It may clear up with treatment but can persist for months to years. People with long-term lesions of the mucous membranes are at greater risk of squamous cell carcinoma — a form of skin cancer. In these cases, a doctor may advise regular examinations to monitor any changes in the mucous membranes or the skin. It’s also important to stop any tobacco use because tobacco raises your risk of squamous cell carcinoma.
Lichen planus on the skin usually clears without treatment within several months, but it may take as long as two years. Mild symptoms typically require only self-care measures and periodic observation by your doctor. More-bothersome symptoms may be treated with ointments or creams to reduce inflammation and itching.
Treatment may include:
- Phototherapy with ultraviolet light
- Cream or ointment applied to the skin (topical medication) containing corticosteroids
- Cream or ointment containing a steroid-sparing immune-modulating medication, such as imiquimod (Aldara) or tacrolimus (Protopic)
- Pills taken by mouth (oral) corticosteroid medications, in severe cases
If you have lichen planus of the mucous membranes, treatment is often challenging and may take years. Oral corticosteroid medications in addition to high-potency corticosteroids applied to the affected areas are often prescribed in these cases.
Self-care measures can help reduce the itching and inflammation caused by lichen planus. These include:
- Tub soaks with colloidal oatmeal (Aveeno, others)
- Cool compresses
- Hydrocortisone cream or ointment, containing at least 1 percent hydrocortisone
- Over-the-counter oral antihistamines, such as diphenhydramine (Benadryl, others), if itching is severe