What should you know about a bug bite rash?

Bites may appear on exposed skin and can be grouped or arranged in a line. Contact dermatitis may match the shape of a product or plant exposure. Heat rash favors sweaty, covered areas, while intertrigo affects skin folds. Scabies often causes intense night-time itch and can involve household contacts. Ringworm usually has a scaly advancing edge. Atopic dermatitis and psoriasis can produce recurrent itchy or scaly patches, and a drug rash can follow a new medicine.

The location, surface, timing, and symptoms around the rash are more useful than the word bite. Photograph it before applying a new cream, and note recent exposures.

Wash gently, pat dry, and use a cool compress. Wear loose clothing and avoid heat, fragranced products, and scratching. Do not use leftover prescription creams or combine several treatments without advice. If scabies or ringworm is suspected, avoid sharing towels and arrange a clinical assessment because the treatment is different from simple bite care.

Get urgent help for breathing difficulty, throat or tongue swelling, faintness, or a rapidly developing widespread reaction. Arrange prompt care if the rash is rapidly expanding, hot and painful, draining pus, accompanied by fever, blistering, or affecting the eyes, mouth, or genitals. Persistent itch or repeated outbreaks also deserve a diagnosis.

What features make this look like a bite rather than dermatitis, scabies, ringworm, or a drug rash? Do I need testing or treatment for infection? Which products should I stop, and how should I prevent scratching?