Lichen planus is a skin rash triggered by the immune system. It’s not currently known why this immune response occurs. There may be several contributing factors, and each case is different. Potential causes include:
Sometimes lichen planus occurs along with autoimmune disorders.
While it may be uncomfortable, in most cases lichen planus is not a serious condition. It’s also not contagious.
However, there are some rare variations of the condition that may be serious and painful. These variations can be treated with topical and oral medications to reduce symptoms, or by using drugs that suppress the immune system.
Some of the most common symptoms of lichen planus include:
- purplish-colored lesions or bumps with flat tops on your skin or genitals
- lesions that develop and spread over the body for several weeks or a few months
- itching at the site of the rash, which commonly appears on the wrists, lower back, and ankles
- lacy-white lesions in the mouth, which may be painful or cause a burning sensation
- blisters, which burst and become scabby
- thin white lines over the rash
The most common type of lichen planus affects the skin. Over the course of several weeks, lesions appear and spread.
Lichen planus of the skin usually goes away on its own
Oral lichen planus can clear up
Besides the skin, mouth, or genitals, lesions can occur in other areas. These may include:
- mucous membranes (such as the esophagus)
- the scalp
But lesions in these areas are less common.
Lichen planus develops when your body attacks your skin or mucous membrane cells by mistake. Doctors aren’t sure why this happens, but there’s evidence genes and environmental factors may play a role.
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.
Specifically, lichen planus can run in families and certain immune system cells are linked to the condition.
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.
Certain environmental factors may also cause the condition, including metal dental fillings and some medications.
Lichen planus can occur in anyone, at any age. But there are certain factors that make some people 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:
- metals, like mercury, copper, and gold
- other medications
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.
Tests can include:
For mild cases of lichen planus, you may not need any treatment. If the symptoms are uncomfortable or severe, 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, which are related to vitamin A and are taken topically or orally
- corticosteroids, which reduce inflammation and can be topical, oral, or given as an injection
- antihistamines, which reduce intense itching
- nonsteroidal creams, which are applied topically and can suppress your immune system and help clear up the rash
- light therapy, which treats lichen planus with ultraviolet light
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
- avoid scratching
- apply cool compresses 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 acidic, spicy, or sharp foods
- avoid alcohol and mouthwash that contains alcohol
- use a prescribed lidocaine solution (that’s swished in the mouth) for pain relief
- eat soft foods if your mouth is sore
- keep up with regular dental visits
Genital lichen planus
- avoid soap and wash with plain water
- use a skin softener, such as petroleum jelly before and after urination
- apply an ice pack wrapped in a towel to soothe itching and swelling
- avoid tight clothing
Talk with your doctor before adding OTC products to your treatment plan. This way you’ll be certain that nothing you might take will interact with the prescription medications you’re taking.
Lichen planus can be difficult to treat if it develops on your vagina or vulva. This can lead to pain, scarring, and discomfort during sex.
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
People with erosive lichen planus are also at risk for skin infections.
Lichen planus can be uncomfortable, but is very often not dangerous. With time, and a combination of home and prescription treatments, the rash can go away.
Seeing your doctor for a diagnosis and following a self-care plan can help on the road to recovery.