The cause of lichen planopilaris is unknown, states Mayo Clinic. It may be triggered by hepatitis C infections, the hepatitis B vaccine, the flu vaccine, exposure to certain pigments and chemicals, NSAIDs, and certain heart disease or blood pressure medications. It is commonly known as lichen planus.
American Academy of Family Physicians explains that lichen planus can affect any mucosal or cutaneous surface of the body including the genitals, mouth, skin and scalp. It is an autoimmune, inflammatory disorder that causes the body to develop numerous small, benign lesions. There is no cure and that all treatment is aimed at relieving discomfort caused by the lesions.