Discoid eczema, also called nummular eczema or discoid dermatitis, causes round or oval patches of inflamed skin. It can persist for weeks or months and may return in the same places. It is not contagious.
Symptoms
- One or more circular or oval patches
- Intense itching, often worse at night
- Small blisters, swelling or oozing in an early flare
- Dry, cracked, crusted or scaly skin later
- Temporary lighter or darker skin after healing
The centre may clear and create a ring-shaped patch that resembles ringworm. Because fungal infection and other skin conditions can look similar, a new circular rash should be assessed when the diagnosis is uncertain.
Causes and triggers
The exact cause is not known. Very dry skin, cold or dry weather, an insect bite, a minor burn or contact with an irritant may trigger a flare. Some medicines have been associated with discoid eczema, but prescribed medicine should never be stopped without medical advice.
Treatment and skin care
Regular emollients help restore the skin barrier. A clinician may recommend a topical corticosteroid for inflamed patches. Avoid fragranced soaps, bubble baths and products that irritate the skin. Use prescribed treatments for the recommended duration and continue moisturising when the rash improves.
When to seek medical advice
See a pharmacist or healthcare professional if you develop circular eczema patches, the diagnosis is uncertain or treatment is not working. Seek prompt advice if a patch becomes increasingly painful, hot, swollen, heavily weeping or covered with yellow crust, or if you develop fever or feel unwell. These can be signs of infection.
Sources
Reviewed: 28 August 2026