Overview
Nummular dermatitis is a specific form of eczema in which the rash forms coin-shaped lesions instead of the general patches of redness that characterize usual eczema. The round lesions are often red, scaly, and itchy. This particular form of eczema is easy to confuse with other diagnoses; sometimes the lesions look just like ringworm, but the treatment for these conditions is different. Just like with eczema, the cause of nummular dermatitis is not well understood, but it seems to be more common in people who have allergies, those who live in cold or dry regions, and in people who have sensitive skin in general. The treatment is similar to that for eczema: keep the skin hydrated by reducing bathing and applying frequent moisturization. A doctor might also prescribe a steroid cream to help with the healing. Nummular dermatitis, as well as the other eczema-type rashes, is not contagious.