The immune system causes a skin rash called Lichen planus. It is not known why this immune response occurs. Each case is different and may be contributed by several factors. Potential causes include:

Sometimes lichen planus occurs along with autoimmune disorders.

It is not a serious condition if you have lichen planus. It is not infectious.

There are some rare variations of the condition that may be serious and painful. The variations can be treated with drugs that suppress the immune system.

The most common symptoms of lichen planus are:

  • purplish-colored lesions or bumps with flat tops on your skin or genitals
  • The body can be colonized by these types of tumors for several weeks or a few months.
  • itching at the site of the rash, which commonly appears on the wrists, lower back, and ankles
  • There are white blisters in the mouth.
  • blisters, which burst and become scabby
  • There are thin white lines over the rash.

Skin

The skin of the most common type of lichen planus is affected. Over the course of several weeks, there are some small tumors.

Lichen planus of the skin usually goes away on its own within 1 to 2 years. After the rash is gone, the skin in the affected area may appear darker.

Oral

Oral lichen planus can clear up within 5 years but often comes back. If the rash is caused by medication, it usually goes away once you’re no longer taking the medication.

There are other areas where there can be skin, mouth, or genitals. These may include:

  • The serous membranes are called the mucous membranes.
  • The nails have nails.
  • The head.

There are less common diseases in these areas.

Lichen planus develops when your body attacks your skin. There is evidence that genes and environmental factors may play a role in this.

Genetics

Research published in 2021 says certain factors point to genetic susceptibility. This means your genes may make it more likely for you to develop lichen planus.

Certain immune system cells are linked to the condition, and can run in families.

Viral infection

Lichen planus may also be triggered by a viral infection. A large 2021 study found there’s a link between hepatitis C infection and chronic inflammatory skin disease, including lichen planus. Other viruses, such as certain types of herpes viruses, may also cause lichen planus.

Environmental factors

Certain environmental factors may also cause the condition, including metal dental fillings and some medications.

Anyone can have Lichen planus. Some people are more likely to develop the condition.

The skin form of lichen planus occurs in both sexes equally, but females are more likely to get the oral form. It’s most common in middle-aged people.

Other risk factors include having family members who’ve had lichen planus, having a viral disease like hepatitis C, or being exposed to certain chemicals that trigger the condition. These triggers may include:

  • Antibiotics.
  • Mercury, copper, and gold are metals.
  • Dehydration.
  • Other drugs

Anytime you see or feel a rash on your skin, or lesions in your mouth or on your genitals, you should talk with a doctor as soon as possible.

Your primary care doctor may send you to a dermatologist if a diagnosis of lichen planus is not obvious, or if your symptoms are making you very uncomfortable.

Your primary care doctor or dermatologist may be able to tell that you have lichen planus simply by looking at your rash. However, a rash from other conditions can look like lichen planus. To confirm the diagnosis, you may need further tests.

Testing

The tests can include:

  • a biopsy, which means taking a small sample of your skin cells to view under a microscope
  • an allergy test, to find out if you’re having an allergic reaction
  • There are tests for the disease, including a test for hepatitis C.

You may not need treatment for mild cases of lichen planus. If the symptoms are not comfortable, your doctor may prescribe medication or you may be able to find symptom relief with home treatments.

Is there a cure for lichen planus?

There’s no cure for lichen planus, but medications that treat the symptoms can be helpful, and some may even be able to target a possible underlying cause. Medications often prescribed include:

  • retinoids are related to vitamins A and B.
  • corticosteroids, which reduce inflammation and can be topical, oral, or given as an injection
  • antihistamines, which reduce intense itching
  • Nonsteroidal creams can help clear up the rash by suppressing the immune system.
  • light therapy, which treats lichen planus with ultraviolet light

Home treatments

There are a few things you can try at home to complement your prescription treatments. The American Academy of Dermatology recommends these methods for skin lichen planus:

  • soak in an oatmeal bath
  • “Don’t scratch.”
  • Cool compress to a rash.
  • Use OTC anti-itch creams.

You might want to try different home treatments and self-care strategies for lichen planus on other parts of the body as well:

Oral lichen planus

  • Avoid eating spicy, acidic, or sharp foods.
  • Alcohol and alcohol-laden products are not advisable.
  • A prescribed lidocaine solution is used for pain relief.
  • If your mouth is sore, eat soft foods.
  • Keep up with your dental visits.

Genital lichen planus

  • Do not wash with soap or plain water.
  • Before and after urinating, use a skin softener.
  • An ice pack wrapped in a towel is a good way to soothe itching.
  • Avoid tight clothing.

Talk with your doctor before you add OTC products. You will be certain that nothing you take will interact with the prescription medications you are taking.

If you develop Lichen planus on your vagina or vulvar, it can be difficult to treat. This can cause pain, scarring, and even make you uncomfortable.

The condition can also cause discoloration of the skin, wherever it appears on the body.

Developing lichen planus can also increase your risk of squamous cell carcinoma. This is particularly the case if you have the erosive form of lichen planus. The increase in risk is small, but you should talk with your doctor for routine skin cancer examinations.

People with erosive lichen planus are at risk for skin infections.

Lichen planus can be uncomfortable, but not dangerous. The rash can be gone with a combination of home and prescription treatments.

It is possible to recover if you see your doctor for a diagnosis and follow a self-care plan.