Lichen planus is an inflammatory rash that can affect both the skin and the inside of the mouth. It is named lichen planus because the rash looks like the flat growing moss that spreads over rocks or trees in the forest.
Lichen planus can be differentiated from eczema or psoriasis as it is lilac or violet in color. It is not contagious to others nor is it an inherited condition. Dermatologists believe it is some form of an autoimmune disease. Lichen planus is the type of rash that will flare up and ease, but not really go entirely away for years.
The rash appears like purple, flattened bumps usually on the inner forearm, wrists or ankles and can be quite itchy. Sometimes lacy white lines appear called Wickman’s striae. The rash usually does not leave scars after it heals but the skin may develop a brown discoloration, which may take a long while to fade.
White patches or lacy lines can appear inside the cheeks, gums, lips or tongue. Sometimes a dentist first finds lichen planus is present during a dental visit. Sores may appear in the mouth, which burn or are painful.
Lichen planus occurs more often to those who are middle aged and equally to men and women. While the cause is unknown, there are situations that seem to trigger an outbreak of the rash. Exposure to certain medications such as antibiotics, diuretics or certain heart medications may cause the rash to develop. Other substances such a gold, dyes or arsenic can cause lichen planus. People with hepatitis C are also at risk.
Antihistamines are commonly used to control itching. Topical steroids are used to decrease inflammation. Sometimes a low dose oral steroid may be tried for persistent cases. Topical retinoic acid creams are useful at reducing both itching and inflammation and they aid in the healing process.
If mouth lesions are particularly painful, a dentist may prescribe oral lidocaine mouth swishes to soothe the tissue. Alternative ways to calm the itch of lichen planus are to take baths using products such as Aveeno and using aloe vera gel has also been found to be helpful.