Lichen Planus – Information on Lichen Planus

Lichen planus (LP) is a pruritic, papular eruption characterized by its violaceous color; polygonal shape; and, sometimes, fine scale. It is most commonly found on the flexor surfaces of the upper extremities, on the genitalia, and on the mucous membranes. LP is most likely an immunologically mediated reaction. See Oral Lichen Planus for more information on this variant of LP.

Lichen planus is an uncommon disorder involving a recurrent, itchy, inflammatory rash or lesion on the skin or in the mouth. The exact cause is unknown, but the disorder is likely to be related to an allergic or immune reaction.
Lichen planus may also affect the scalp, the nails or the inside of the mouth. 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. Sometimes lichen planus affects areas of skin where you had a cut or burn.

The disorder has been known to develop after exposure to potential allergens such as medications, dyes, and other chemical substances. Symptoms are increased with emotional stress, possibly because of changes in immune system during stress.
Lichen planus usually heals on its own within two years. Your doctor can prescribe medication such as antihistamines to relieve itching. Corticosteroids, which can be injected into the affected areas, taken by mouth, or applied to the skin, also help control inflammation and itching. People with severe lichen planus may benefit from psoralens plus ultraviolet A (PUVA) treatment, which combines drugs to make the skin more sensitive to ultraviolet light (psoralens) with phototherapy. Medicated mouthwashes can help relieve pain from ulcers in the mouth.

In most cases the rash is typical and a doctor can diagnose the condition from the look of the rash. If there is doubt, then a small sample of affected skin can be taken (a biopsy) under local anaesthetic. The biopsy sample is looked at under a microscope. Characteristic changes in the skin can be seen which confirms the diagnosis.

There is no known cure for skin lichen planus, but treatment is often effective in relieving itching and improving the appearance of the rash until it goes away. Since every case of lichen planus is different, no one treatment does the job. Topical corticosteroids are very useful. Antihistamines may be prescribed to relieve itching. Extensive cases may require the use of oral corticosteroid (cortisone, prednisone) for a number of weeks. This usually shortens the duration of the outbreak. For severe cases powerful treatments include photo chemotherapy light treatment (PUVA), the retinoids drugs (Soriatane and Accutane), Neoral and Plaquenil.

The cause of lichen planus is not known; however, there are cases of lichen planus-type rashes (known as lichenoid reactions) occurring as allergic reactions to medications for high blood pressure, heart disease and arthritis. These lichenoid reactions are referred to as lichenoid mucositis (of the mucosa) or dermatitis (of the skin). Lichen planus has been reported as a complication of chronic hepatitis C virus infection and can be a sign of chronic graft-versus-host disease of the skin.

LP of the mouth most commonly occurs inside of the cheeks, but can affect the tongue, lips, and gums. Oral LP is more difficult to treat and typically lasts longer than LP on the skin. Fortunately, many cases of LP of the mouth cause minimal problems. About one in five people who have oral LP also have skin LP.
Patients with lichen planus are sometimes tense and nervous, and episodes of dermatitis may be temporarily related to emotional crises. Measures to relieve anxiety are helpful. Topical corticosteroids are often useful. Topical tretinoin cream 0.05% applied to mucosal lichen planus followed by topical corticosteroid cream may be beneficial.