What should you know about brown ringworm?

Ringworm is not caused by a worm. The infection can spread outward, creating a more active edge with scale while the centre looks calmer. On deeper skin tones, inflammation may look brown, grey-brown, or purple-brown rather than bright red. Darkening can remain after the infection settles. A rash elsewhere may resemble this pattern, including eczema or irritation, so appearance alone cannot confirm the cause.

A clinician may inspect the border, ask about pets or close contacts, and examine other affected areas. Testing a skin sample can help when the pattern is unusual or treatment has not helped.

Keep the area clean and dry, avoid scratching, and do not share towels, clothing, or razors. A pharmacist or clinician can guide you toward topical antifungal treatment for a small area; more widespread, stubborn, or hair-bearing infection may need oral antifungal treatment. Use the recommended product for the full advised course, even if the border fades early. Avoid steroid cream alone unless a clinician has told you to use it, because it can disguise fungal changes and allow them to spread.

Arrange a medical review if the rash is spreading, painful, oozing, affecting the scalp or nails, or failing to improve with appropriate antifungal care. Seek prompt help for swelling around the eye, fever, rapidly worsening tenderness, or widespread blistering. Children, people with diabetes, and people with reduced immune function may need earlier assessment.

Ask whether the brown edge still shows active scale, whether a sample is needed, which treatment is suitable for the body area, and how to reduce spread to household members or pets.