Red itchy rash: possible causes and when to seek care

Atopic dermatitis often causes recurring itchy, dry inflammation, while contact dermatitis follows exposure to a product, plant, metal, or chemical. Heat rash develops when sweat is trapped, and intertrigo affects rubbing, moist folds. Psoriasis can form persistent scaly plaques. Ringworm may create an expanding scaly edge, whereas scabies often causes intense itch and may affect close contacts. A drug rash can begin after a new medicine or dose change. Record when it started, where it began, what it looks like, and any new exposure; these details are more useful than judging the colour alone.

Cool the skin, wear loose clothing, and wash with a gentle fragrance-free cleanser. Apply a plain moisturiser if the skin is dry and avoid scratching, scrubbing, and newly introduced products. Do not stop a prescribed medicine without advice, but contact the prescriber promptly if the rash followed a new medicine. Avoid sharing towels or bedding when an infection such as ringworm or scabies is possible. Arrange review if the rash persists, spreads, or repeatedly returns.

Seek emergency help for breathing difficulty, swelling of the lips or tongue, faintness, widespread blistering, skin peeling, painful mouth or eye sores, or a rapidly worsening rash after a medicine. Get prompt medical advice for fever, pus, severe pain, purple spots, facial or genital involvement, or a rash in an infant. Urgency depends on these warning signs, not simply on how common a rash is.

Could this be contact dermatitis, heat rash, infection, or a drug rash? Which products should I avoid? Do I need treatment for other household members? What symptoms should prompt emergency care?