Neurodermatitis (lichen simplex chronicus)

For a lay person:

Neurodermatitis, also called lichen simplex chronicus, is a patch of thick, itchy skin caused by repeated scratching and rubbing. It often starts with a small itch that becomes an itch-scratch cycle, and stress can make it worse. Common sites are the neck, wrists, ankles, scalp and genital area.

For a trained medical person:

Chronic rubbing and scratching produce lichenification with epidermal hyperplasia, often on a background of atopy, anxiety or an underlying itch such as eczema or neuropathic itch. Diagnosis is clinical, with biopsy when the diagnosis is uncertain and assessment for underlying causes. Management aims to break the itch-scratch cycle with potent topical or intralesional corticosteroids, occlusion, antipruritics, and addressing stress or underlying disease.

In Chinese medicine:

Liu and Tseng's textbook differentiates this condition into these patterns: Blood-Heat Generating Wind, Failing to Nourish Skin; Blood Deficiency, Wind Dryness Failing to Nourish Skin; Wind-Evil Chronic Stagnation, and Failing to Nourish Qi and Blo od. Treatment follows the pattern a patient presents with, not the Western diagnosis alone.

When to get help: See a doctor if the skin bleeds, oozes or looks infected, if itching stops you sleeping, or if a patch changes or does not respond to treatment. Some herbal creams have been found to contain undeclared steroids.