What is lichen planus (lye-kenplan-us)?
Lichen planus is a benign (not cancer) condition that affects either the skin or the lining of the mouth. Occasionally both areas will be affected. We don’t know what causes lichen planus, but we do know that lichen planus is not caused by an infection (bacteria, virus or fungus) or any identifiable habit (smoking, foods, etc.). What we believe is happening in lichen planus is that the immune cells, which normally protect us by destroying bacteria or viruses, get confused and start attacking the skin or the lining of the mouth. What does lichen planus look like? On the skin, lichen planus appears as small, itchy, red-purple, flat-topped bumps that occur in clusters on the forearms and thighs primarily. In the mouth, lichen planus may take on two basic forms: (1) Reticular lichen planus gets its name from the lace-like pattern of fine white lines that appear most commonly on the inside of the cheeks. It may also be seen on the gums and on the top of the tongue. Usually reticular lichen
