Lichen planus is a relatively common skin disease that comes in episodes lasting months to years. It appears as purple or reddish-purple bumps on the skin. The bumps have flat tops and are uneven in shape. 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. Skin LP affects men and women equally, but oral LP affects women twice as often as men. LP occurs most frequently in middle-aged adults. The cause of LP is not known. Lichen planus can appear on any area of the skin. The most common areas are the inner wrists, the forearms and the ankles. Lichen planus in children is rare. Occasionally oral lichen planus involves the throat or the esophagus. 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 may cause a small number of skin lesions or less often affect a wide area of the skin and mucous membranes. In 85% of cases it clears from skin surfaces within 18 months but it may persist longer especially when affecting the mouth or genitals.
Lichen planus usually heals on its own within two years. 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 is generally not harmful and may resolve with treatment. It appears to be a reaction in response to more than one provoking factor. About 1 in 100 people develop lichen planus. It can also cause ulcers in the mouth but this is uncommon. Lichen planus may be associated with several other disorders, most notably hepatitis C. More than two thirds of cases occur in people aged 30-60 years. 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. Lichen planus may also affect the scalp, the nails or the inside of the mouth. On the scalp, lichen planus may cause hair loss. The expression or unmasking of the lichen planus antigen may be induced by drugs (lichenoid drug reaction), contact allergens in dental restorative materials or toothpastes (contact hypersensitivity reaction), mechanical trauma (Koebner phenomenon), viral infection, or unidentified agents. It is not a cancer or an infectious disease that can be passed on and it does not run in families.
Causes of Lichen planus
The common causes and risk factor’s of Lichen planus include the following:
The exact cause is unknown, but the disorder is likely to be related to an allergic or immune reaction.
Medical conditions: Medical conditions associated with oral lichen planus include lichen planus of the skin, hypertension, diabetes and peptic ulcers.
The disorder has been known to develop after exposure to potential allergens such as medications, dyes, and other chemical substances.
It can also cause ulcers in the mouth but this is uncommon.
One theory is that the immune system may be ‘triggered’ by a virus or other factor in the environment to attack cells on the skin which leads to the inflammation.
Lichen planus may be associated with several other disorders, most notably hepatitis C.
Certain medications, such as some of those used to treat arthritis, heart disease, high blood pressure and malaria, may trigger oral lichen planus in some people.
Symptoms of Lichen planus
Some sign and symptoms related to Lichen planus are as follows:
Itching in the location of a lesion, mild to severe.
Ridges in the nails ( nail abnormalities ).
Metallic taste in the mouth.
The spots of lichen planus are flat-topped, pink-purple in colour, and usually 3mm to 5mm wide.
Mouth ulcers also arise causing soreness that is made worse by hot or spicy food.
Treatment of Lichen planus
Here is list of the methods for treating Lichen planus:
Measures to relieve anxiety are helpful.
In more severe cases, physicians may recommend oral medications or therapy with ultraviolet light.
Topical tretinoin cream 0.05% applied to mucosal lichen planus followed by topical corticosteroid cream may be beneficial.
Occlusive dressings may be placed over topical medications to protect the skin from scratching.
Topical retinoic acid cream (a form of vitamin A) and other ointments or creams may reduce itching and inflammation and may aid healing.
Ultraviolet light therapy may be beneficial in some cases.