Lichen planus is a condition that forms a very itchy rash on the skin or in the mouth.
The exact cause of lichen planus is unknown. It may be related to an allergic or immune reaction.
Risks for the condition include:
Lichen planus mostly affects middle-aged adults. It is less common in children.
Mouth sores are one symptom of lichen planus. They:
Skin sores are another symptom of lichen planus. They:
Other symptoms of lichen planus are:
Exams and Tests
Your health care provider may make the diagnosis based on the appearance of your skin or mouth lesions.
A skin lesion biopsy or biopsy of a mouth lesion can confirm the diagnosis.
The goal of treatment is to reduce symptoms and speed healing. If your symptoms are mild, you may not need treatment.
Treatments may include:
Lichen planus is usually not harmful. Most often it gets better with treatment. The condition often clears up within 18 months, but may come and go for years.
If lichen planus is caused by a medicine you are taking, the rash should go away once you stop the medicine.
When to Contact a Medical Professional
Call your provider if:
James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM. Lichen planus and related conditions. In: James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM, eds. Andrews' Diseases of the Skin. 13th ed. Philadelphia, PA: Elsevier; 2020:chap 12.
Patterson JW. The lichenoid reaction pattern ('interface dermatitis'). In: Patterson JW, ed. Weedon's Skin Pathology. 4th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2016:chap 3.
Review Date: 10/14/2018
Reviewed By: Michael Lehrer, MD, Clinical Associate Professor, Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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