Definition

Lichen planus is a long term skin condition. It can lead to swelling and irritation of the skin, scalp, and fingernails. It can also affect the inside of the mouth and genitals. Treatment can help manage discomfort.

Section of Skin with Lichen Planus Copyright © Nucleus Medical Media, Inc.

Causes

The exact cause of lichen planus unknown. It may be due to the immune system attacking the skin. It may also be due to genes.

Risk Factors

Lichen planus is more common in those aged 30 to 60 years.

Other things that may raise the risk are:

• Dental materials used in fillings
• Certain medicines
• Stress
• Certain infections, such as hepatitis C

Symptoms

Symptoms may come and go for months to a few years. Symptoms of lichen planus may be:

• Itchy, flat, purplish bumps or white-lined scaly patches on:
  • The wrists, arms, or legs
  • The foot and ankles
  • Below the neck and above the waist
  • The genitals
  • The inside of the mouth
• Hair loss
• Nails with ridges, grooves, or splitting

Diagnosis

The doctor will ask about symptoms and health history. A physical exam will be done. Lichen planus is often diagnosed by how it looks. A skin doctor may need to look at the skin.

If the diagnosis is unclear, other tests may be done, such as:

• Blood tests
• A skin biopsy—a sample of skin is taken and tested

Treatment

Treatment depends on how severe the symptoms are. It also depends on what part of the body is affected. The goal is to ease discomfort and inflammation.

Medicines may include:

• Antihistamine skin cream or pills—to ease itching
• Steroid skin cream, pills, or injections—to reduce inflammation
• Retinoids and other skin creams—to reduce patches in the mouth
• Lidocaine skin cream—to help ease pain

If symptoms are severe, medicines may be given to lower the immune system.

Ultraviolet light therapy may help if there are many skin patches. It is used with pills that make it more effective.

Prevention

There are no current guidelines to prevent lichen planus.