Ringworm marks on skin: what they may mean and what to do

Ringworm is a fungal infection of the outer skin. The edge may be more active than the centre, with scaling, itch or a raised rim. As inflammation fades, the area can look darker or lighter than nearby skin; that leftover colour is not proof that fungus is still present. A changing rash can also have other causes, so appearance alone cannot confirm the diagnosis.

Keep the area clean and dry, avoid scratching, and do not share towels, clothing or sports equipment. A clinician or pharmacist can guide you toward a suitable topical antifungal treatment for skin ringworm. Use it exactly as directed and give the skin time to recover. If the area is extensive, recurrent, or not improving, assessment may be needed and oral antifungal treatment could be considered.

Arrange medical review if the rash involves the face, scalp, nails or a large area, or if it is painful, oozing, rapidly spreading or associated with fever. Seek advice when treatment has not helped, because eczema, psoriasis and other rashes can resemble ringworm and need different care.

Could this be active ringworm or a post-infection colour change? Does the location require a different treatment? How should I reduce spread to household members? What signs would mean I need a follow-up examination?