What It Is, Causes, and Treatment

Lichenoid dermatitis is one of the least common forms of eczema, a skin disorder characterized by inflammation and an itchy rash. Older adults are most likely to experience lichenoid dermatitis, but it can develop at any age. The skin disorder presents with raised bumps on the skin and a purplish tint.

This article discusses the causes, symptoms, and treatment options for lichenoid dermatitis.

What Is Lichenoid Dermatitis?

Lichenoid dermatitis is a type of eczema. It is an inflammatory skin disorder that develops when there is damage to the basal keratinocytes, which are cells found in the skin’s basal layer (the innermost layer). The skin cells are damaged by what is known as apoptosis, meaning the death of a cell from within.

The rash that develops in lichenoid dermatitis is often purplish and forms in raised bumps on the ankles, lower back, wrists, or forearms. In some cases, it can also develop on the scalp, around the nails, or in the genital area.

What Causes Lichenoid Dermatitis?

The exact cause of lichenoid dermatitis isn’t well known, but many medical professionals believe it develops from taking certain medications or contracting a viral infection.

Some of the most common medications that cause lichenoid dermatitis are:

The viral infection most often associated with lichen dermatitis is hepatitis C.

Symptoms of Lichenoid Dermatitis

The main characteristic of lichenoid dermatitis is raised bumps on the skin. The spots can be small but may develop into larger, scaly rashes. Other symptoms are:

• A symmetrical rash that is evenly distributed on both sides of the body
• A rash that develops on areas most often exposed to the sun, including the ankles, wrists, and forearms
• Itchiness
• Swelling
• Discoloration of the skin (a purple hue)

How Is Lichenoid Dermatitis Treated?

The first-line treatment for lichenoid dermatitis depends on the cause. If it’s caused by medication, a healthcare provider may advise you to stop taking the drug and will prescribe another treatment that is less likely to cause the same reaction.

If the medication cannot be stopped because it’s treating something more severe like cancer, you may be given a reduced dose to help combat the reaction, as well as a treatment for the rash, such as topical steroid cream. In the most severe cases, oral steroids may provide relief from the rash.

If a viral infection is causing the rash, treatment will be done to remedy the infection before treating the rash itself. 

Summary

Lichenoid dermatitis is an itchy rash that develops from an adverse reaction to a medication or a viral infection. It is considered the least common form of eczema but still affects many people. When the rash develops, it starts as small, raised bumps that are purple but can progress to larger scaly patches if not treated early on. Treatment will depend on the cause.

If medication is causing the rash, a healthcare provider will lower your dose, remove the drug from your treatment plan, or switch you to something else that works but doesn’t cause an adverse reaction. If an infection is the cause, it will likely be treated with drugs and creams and ointments to help symptoms. The rash itself isn’t harmful but can indicate a condition requiring medical attention.