Lichen planus (LP) is a relatively common condition characterised by an inflamed, extremely itchy rash that can affect many different parts of the body. The most commonly affected sites include the wrists, ankles and lower back. Other areas such as the mouth, genitalia, nails and scalp are also affected. It is usually seen in adults over the age of 40 and is not known to be a hereditary condition. It is not infectious, and both men and women are equally susceptible.
What causes Lichen Planus?
Unfortunately, it is still not known what causes this disease to occur, though there is some evidence to suggest that it could be caused by a malfunction in the body’s immune system. Some drugs can also cause a temporary LP-like rash to develop which resolves slowly once the offending medication is stopped.
What are the symptoms/types of Lichen Planus?
There are many different forms of lichen planus which differ in appearance and the parts of the body they affect (see images). Typically, LP appears as multiple purple/red shiny, flat-topped bumps that form on the skin in a symmetrical distribution across the body. As the individual bumps heal they change colour from red to purple, then to grey or brown. Sometimes there is scale on the surface of the bumps. Lichen Planus can form in line-shaped (linear) or ringlet-shaped (annular) areas and sometimes appears in scars.
What Lichen Planus treatments are available?
Unfortunately, no treatment has been found to cure LP but thankfully in most patients it will resolve by itself within 1-2 years. However, about 20% of patients experience a recurrence, which can be many years after the initial episode. The aim of treatment is therefore to control symptoms.
Potential treatment options include:
Emollients to prevent skin dryness
Steroid creams or tablets to decrease the inflammation
Ultraviolet light treatment (phototherapy)
Drugs to calm the body’s immune system such as tacrolimus or ciclosporin
Drugs to slow down the rate of turnover of skin cells such as acitretin
Frequently asked questions
The itching is the key symptom that affects people with Lichen Planus. The appearance of the rash can be distressing for some, especially if it occurs in intimate areas such as the genitalia. Furthermore, as the skin lesions heal, darkly pigmented blemishes may appear in their place which can take months or even years to resolve, particularly in those with a darker skin tone. If LP occurs on the scalp it can lead to patchy hair loss which may be permanent. Pitting, ridging or complete detachment of the nails eroded by LP can also look unsightly.
For further information please visit the NHS website and read the British Association of Dermatology patient advice leaflet.