Lichen Planus

Lichen planus is a chronic recurrent rash that occurs due to inflammation of your skin and mucous membranes. On the skin, the rash is characterized by small, purplish, often itchy, flat-topped, many-sided (polygonal) bumps that can grow together into rough, scaly plaques on the skin. 

Mouth, vagina, and other areas covered by a mucous membrane are the most commonly affected areas of lichen planus inflammation. Lichen planus forms lacy white patches, sometimes with painful sores. 

It affects about one in one hundred people worldwide, mostly affecting adults over the age of 40 years. 

About half those affected have oral lichen planus, which is more common in women than in men and about 10% of the population have lichen planus of the nails. It is a T cell-mediated autoimmune disease, in which inflammatory cells attack a protein present in the skin and mucosal keratinocytes. 

The reason for this abnormal immune response is unknown. Lichen planus is not contagious thus, you cannot get this disease from someone else and cannot give it to anyone. Lichen planus is not a type of cancer. 

The symptoms of lichen planus vary depending on the areas affected.

The common symptoms are:

• Purplish-colored lesions or flat-topped bumps on your skin or genitals
• Itching blisters occurring mostly on the inner forearm, wrist or ankle, but sometimes on the external genitals 
• White spots or patches in the mouth — inside the cheeks or on the gums, lips or tongue
• Painful oral or vaginal ulcers
• Hair loss and scalp discoloration
• Nail damage or loss
• Lesions that develop and spread over the body 
• Itching at the site of the rash.

The condition will usually clear up within six to 16 months, but in some cases, proper treatment is needed.

The cause of lichen planus is unknown, though strong evidence suggests that inflammation, controlled by the immune system, gives rise to the lesions.

The contributing factors which trigger lichen planus may include:

• Physical and emotional stress
• Genetic predisposition
• Systemic viral infection, such as hepatitis C, hepatitis B (which might modify self-antigens on the surface of basal keratinocytes)
• Injury to the skin; lichen planus often appears where the skin has been scratched—isomorphic response (koebnerisation)
• Localized skin disease such as herpes zoster—isotopic response
• Contact allergy, such as allergy to metal fillings in oral lichen planus (rare)
• Drugs; gold, quinine, quinidine and others can cause a lichenoid rash
• Certain medications for heart disease, high blood pressure or arthritis
• Chemicals and metals 
• Non-steroidal anti-inflammatory drugs, such as ibuprofen (Advil, Motrin IB, others) and naproxen

A lichenoid inflammation is also notable in graft-versus-host disease, a complication of bone marrow transplant.

You'll likely start by seeing your family doctor or a general practitioner to receive a diagnosis of lichen planus. You may be referred to a specialist in skin diseases (dermatologist). 

Your doctor will ask you a number of questions so keep details of all signs and symptoms and other important information. The doctor is most likely to ask: 

• When did the bumps or other lesions appear?
• Where on your body have you found the lesions?
• Are the affected areas itchy, painful or uncomfortable?
• How would you describe the severity of the pain or discomfort — mild, moderate or severe?
• Have you recently started new medications?
• Have you recently undergone immunizations?
• Do you take supplements or vitamins, or other nonprescription herbs or medicines? 
• Do you have any allergies?

Your doctor or dermatologist will perform a physical examination to diagnose lichen planus. To confirm the diagnosis, he may perform:

• Biopsy: During a punch biopsy test, your doctor removes a small section of your skin, which is then examined under a microscope for cell patterns characteristic of lichen planus. You'll receive a local anesthetic to numb the site and likely require stitches to close the wound. 
• Hepatitis C tests: a small sample of blood for a lab test to determine if you have hepatitis C, a possible trigger for lichen planus.
• Allergy tests: Your doctor may refer you to an allergy specialist (allergist) to determine whether substances you regularly have contact with may be causing you to have allergic reactions that act as triggers for your condition.

In mild cases of lichen planus, the patient may become normal within weeks or months with local treatments for symptomatic cutaneous or mucosal disease. 

In severe cases, there is no permanent cure for lichen planus but medications could help treating the symptoms and in some cases to target a possible underlying cause. Medications that are often prescribed include:

1. Retinoids, which are related to vitamin A and are taken topically or orally
2. Corticosteroids reduce inflammation and can be topical, oral, or given as an injection
3. Antihistamines reduce inflammation and may be particularly helpful if your rash is triggered by an allergen
4. Nonsteroidal creams are applied topically and can suppress your immune system and help clear up the rash
5. Light therapy treats lichen planus with ultraviolet light

There are no known measures for preventing lichen planus but avoiding certain chemicals and medications may reduce flare-ups in some patients with this disorder. 

Following alternative remedies used for lichen planus are effective, but make sure to consult your doctor before following them:

• Soaking in an oatmeal bath
• Avoiding scratching
• Applying cool compresses to the rash
• Aloe vera gel
• Sulphur mineral baths 
• Vitamin supplements A diet rich in fruit and vegetables 
• Oral and topical herbal medications 
• Cod liver oil supplements
• Using OTC anti-itch creams
• Adding a source of vitamins A, D and an OTC product for your treatment. 

There are several risks associated with lichen planus.

Anyone can develop lichen planus, but the condition most often affects middle-aged adults.

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.

There is some evidence that lichen planus may increase your risk of a skin cancer known as squamous cell carcinoma, though the risk is small. Your doctor may recommend routine screening for evidence of cancerous cells in tissues affected by lichen planus.