Lichen planus (LIE-kun PLAY-nus) is a condition of the skin, hair, nails, mouth and genitals. On skin, lichen planus often appears as purple, itchy, flat bumps that develop over several weeks. In the mouth and genital mucosa, lichen planus forms lacy white patches, sometimes with painful sores.

Mild lichen planus of the skin may not need treatment. If the condition causes pain or intense itching, you may need prescription medicine.


Symptoms of lichen planus vary depending on the part of the body affected. Nail disease usually affects several nails. Symptoms include:

  • Purple, shiny, flat bumps, often on the inner forearms, wrists or ankles.
  • Lines of rash where the skin has been scratched.
  • Lacy white patches on the tongue or inside of the cheeks.
  • Itchiness.
  • Painful sores in the mouth or genitals.
  • Rarely, hair loss.
  • Nail scarring or loss.
  • Dark lines from the tip of the nail to the base.

When to see a doctor

See your health care provider if tiny bumps or a rash appears on your skin for no known reason, such as contact with poison ivy. Also see your health care provider if you have any symptoms related to lichen planus of the mouth, genitals, scalp or nails.

It's best to get a prompt and correct diagnosis because a number of skin and mucous membrane conditions can cause sores and pain.

From Mayo Clinic to your inbox

Sign up for free and stay up to date on research advancements, health tips, current health topics, and expertise on managing health. Click here for an email preview.

To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.


The cause of lichen planus is likely related to the immune system attacking cells of the skin or mucous membranes. It's not clear why this irregular immune response happens. The condition isn't contagious.

Lichen planus may be activated by:

  • Hepatitis C infection.
  • Pain relievers and other medicines.
  • An allergic reaction to the metal in dental fillings.

Risk factors

Anyone can develop lichen planus. It most often affects middle-aged adults. Lichen planus in the mouth is more likely to affect women than men.


Lichen planus can be difficult to treat on the vulva and in the vagina. It can cause scarring and severe pain. Sores on the genitals can make sex painful.

The affected skin and nails might stay slightly darker even after healing.

Oral sores may affect your ability to eat. Oral lichen planus increases the risk of oral cancer. Rarely, lichen planus affects the ear canal. Left untreated, it may lead to hearing loss.

April 04, 2023
  1. AskMayoExpert. Oral lichen planus. Mayo Clinic; 2021.
  2. High WA, et al., eds. Lichenoid skin eruptions. In: Dermatology Secrets. 6th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed Nov. 23, 2022.
  3. James WD, et al. Lichen planus and related conditions. In: Andrews' Diseases of the Skin: Clinical Dermatology. 13th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Nov. 23, 2022.
  4. Lichen planus. American Academy of Dermatology. https://www.aad.org/public/diseases/a-z/lichen-planus-overview. Accessed Nov. 21, 2022.
  5. Aloe. Natural Medicines Comprehensive Database. https://naturalmedicines.therapeuticresearch.com/. Accessed Nov. 21, 2022.
  6. Kusai A, et al. Lichen planus. New England Journal of Medicine. 2018; doi: 10.1056/NEJMicm1802078.
  7. Tziotzios C, et al. Lichen planus and lichenoid dermatoses: Clinical overview and molecular basis. Journal of the American Academy of Dermatology. 2018; doi:10.1016/j.jaad.2018.02.010.
  8. Gupta MK, et al. Review of nail lichen planus: Epidemiology, pathogenesis, diagnosis, and treatment. Dermatologic Clinics. 2021; doi:10.1016/j.det.2020.12.002.
  9. Kelly AP, et al., eds. Nail disorders. In: Taylor and Kelly's Dermatology for Skin of Color. 2nd ed. McGraw Hill; 2016. https://accessmedicine.mhmedical.com. Accessed Nov. 22, 2022.
  10. Goldstein BG, et al. Lichen planus. https://www.uptodate.com/contents/search. Accessed Nov. 21, 2022.
  11. Goldstein GB, et al. Topical corticosteroids: Use and adverse effects. https://www.uptodate.com/contents/search. Accessed Nov. 21, 2022.
  12. Zubair R, et al. What's new in pigmentary disorders. Dermatological Clinics. 2019; doi: org/10.1016/j.det.2018.12.008.
  13. Sominidi Damodaran S (expert opinion). Mayo Clinic. Dec. 12, 2022.