What should you know about the effect of ringworm?

Despite its name, ringworm is caused by fungi rather than a worm. The infection commonly affects the outer layer of skin and may produce a red or darker patch with a more active, scaly edge. It can gradually enlarge, while the centre may look clearer than the border. Itching, cracking, soreness, or burning can occur, especially where sweat and friction collect.

Ringworm may affect the trunk, arms, legs, groin, feet, scalp, or nails, and the appearance varies by body site and skin tone. A rash or scaling can have causes other than ringworm, so a clinician may examine the area and sometimes test a skin sample before choosing treatment. See more about [Skin Rash](/symptoms/skin-rash/) and [Scaly Skin](/symptoms/skin-scaling/).

Keep the affected skin clean and dry, wash your hands after touching it, and avoid scratching. Do not share towels, clothing, hairbrushes, bedding, sports equipment, or footwear until the infection has been assessed and managed. Wash fabrics that touch the area and let shoes dry between uses. Check household pets if they have bald, scaly, or irritated patches, because animals can pass fungi to people.

Use an antifungal medicine according to the label or your clinician’s instructions, and follow the full recommended course even if the rash looks better sooner. A cream may be suitable for some skin infections; scalp, nail, widespread, or persistent infection may require tablets. Learn about [Topical Antifungal Treatment](/treatments/medical-dermatology/topical-antifungal-therapy/) and [Oral Antifungal Treatment](/treatments/medical-dermatology/oral-antifungal-therapy/).

Arrange a dermatology review if the rash involves the scalp or nails, covers a large area, keeps spreading, returns repeatedly, or does not improve with appropriate self-care. Seek prompt care if the skin becomes very painful, hot, swollen, blistered, or produces pus, or if you develop fever or feel significantly unwell. Children, people with diabetes, and people with weakened immunity should seek advice early because infection may be harder to manage.

Ask whether the rash looks like ringworm or needs testing, which treatment form fits its location, how long to use it, and whether close contacts or pets should be checked. Mention any medicines you take, pregnancy or breastfeeding, and previous reactions to antifungal products.