What should you know about planar lichen planus?

Planar lichen planus affects the skin and may produce clusters of firm, flat-topped bumps with fine surface lines. Itching can be prominent, and scratching may create new lesions or irritate existing ones. As bumps settle, they can leave darker or lighter marks that may fade slowly.

The appearance can overlap with other rashes, so a clinician may examine the distribution, mouth or genital symptoms, nails, and scalp. A biopsy or other assessment may be considered when the pattern is atypical or persistent.

Use gentle, fragrance-free cleansing and moisturising, and keep nails short to limit damage from scratching. A clinician may recommend [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) for inflamed areas; more extensive or resistant disease may need another treatment plan, sometimes including [Oral Corticosteroid Treatment](/treatments/medical-dermatology/oral-corticosteroid-therapy/).

Tell your doctor about new medicines, liver concerns, mouth soreness, genital discomfort, hair loss, or nail changes. Do not stop a prescribed steroid suddenly without specific medical advice.

Arrange an appointment for a spreading, very itchy, painful, or unexplained rash, especially if it affects the mouth, genitals, eyes, or nails. Seek prompt care for infected-looking skin, severe pain, facial swelling, or difficulty eating, drinking, or seeing.

How confident are you in the diagnosis, and is testing needed? Which treatment fits the affected sites? How should I use the medicine, protect my skin, and monitor pigment changes or symptoms beyond the skin?