Lichen Planus: Symptoms, Causes and UK Management Guide

Lichen planus is a relatively common inflammatory condition that affects the skin and mucous membranes. In the UK, it is estimated to affect around 1% of the population. Unlike many rashes, lichen planus is not caused by an infection, and you cannot catch it from someone else. Instead, it is thought to be an autoimmune-related response, where the body's immune system mistakenly attacks cells in the skin or lining of the mouth.

Patients often describe the rash as appearing suddenly. The most common form, cutaneous lichen planus, manifests as small, shiny, flat-topped bumps that have a characteristic purple or lilac hue. These bumps often have fine white streaks across them, known as Wickham’s striae. While it can appear anywhere, it most frequently affects the inner wrists, forearms, and ankles.

The symptoms of lichen planus can vary depending on which part of the body is affected. Key signs to look out for include:

• Purple-coloured bumps: These are usually a few millimetres in diameter, flat-topped, and may have a slight shine.
• Intense itching: The rash is often extremely itchy, which can interfere with sleep and daily activities.
• Wickham's Striae: A lace-like pattern of white lines visible on the surface of the bumps.
• Oral symptoms: When it affects the mouth (oral lichen planus), it appears as white patches or streaks on the inside of the cheeks or tongue. This may be painless or cause a burning sensation.
• Nail changes: Nails may become thinned, ridged, or in some cases, stop growing entirely.

According to NHS guidance, the skin rash usually clears within 6 to 18 months, but the oral form can be more persistent and require long-term monitoring.

The exact cause of lichen planus remains unknown, but medical consensus suggests an immune-mediated mechanism. T-cells, a type of white blood cell, become overactive and attack the skin cells. While the trigger isn't always clear, several factors have been associated with flares:

Potential Triggers

• Stress: Emotional stress is frequently cited by patients as a trigger for new flares or worsening symptoms.
• Medicines: Certain medications for high blood pressure, heart disease, or malaria can occasionally cause a 'lichenoid' reaction.
• Metallic fillings: In rare cases of oral lichen planus, an allergy to mercury in dental amalgam may be a factor.
• Hepatitis C: There is a statistical link between Hepatitis C and lichen planus, though most UK patients with the skin condition do not have the virus.

Following NICE (National Institute for Health and Care Excellence) clinical knowledge summaries, the primary goal of treatment is to reduce itching and inflammation. Because the condition often resolves on its own, mild cases may not require treatment other than emollients.

For more symptomatic cases, the following treatments are commonly used:

• Topical Corticosteroids: Potent steroid creams or ointments are the first-line treatment to reduce redness and itch.
• Antihistamines: These may be recommended, particularly at night, to help reduce the sensation of itching and improve sleep.
• Topical Calcineurin Inhibitors: Creams like tacrolimus may be used for sensitive areas where steroid use should be limited.
• Light Therapy (PUVA): For extensive rashes, ultraviolet light treatment under hospital supervision may be necessary.

If you are managing lichen planus, it is important to avoid scratching, as this can lead to the Koebner phenomenon, where new lesions form in areas of skin trauma.

Managing a chronic skin condition like lichen planus can be frustrating, especially when waiting for a traditional GP appointment. You can speak to a GP online in the UK to discuss your symptoms and receive guidance on the best course of action. An online GP can review high-quality photos of your rash, provide a preliminary diagnosis, and advise on suitable over-the-counter or prescription treatments.

If you have been previously diagnosed and are experiencing a flare-up, an online consultation is an efficient way to request a repeat prescription for steroid creams or to discuss the escalation of your treatment plan. They can also provide a private sick note if the itching and discomfort are severely impacting your ability to work.

Beyond medical treatments, there are several steps you can take to manage lichen planus at home:

• Use mild soaps: Fragrance-free cleansers are less likely to irritate inflamed skin.
• Mouth care: If you have oral lichen planus, avoid spicy, acidic, or salty foods that can trigger pain. Use a soft toothbrush and alcohol-free mouthwash.
• Cool compresses: Applying a cool, damp cloth to itchy areas can provide temporary relief without damaging the skin.
• Moisturise: Keeping the skin hydrated with thick emollients can help reduce the urge to scratch.