What should you know about skin irritation rash?

Contact dermatitis can follow exposure to an irritant or allergen, often where a product, metal, plant or chemical touched the skin. Atopic dermatitis often presents with itchy, dry and inflamed skin. Heat rash tends to affect sweaty or occluded areas, while intertrigo develops where skin rubs against skin.

Scabies can cause intense itch with a pattern that may involve household contacts. Ringworm can form a scaly expanding edge. Psoriasis may create well-defined, scaly plaques, and a drug rash can begin after a new medicine. These patterns overlap, so appearance alone cannot confirm a diagnosis.

Stop any newly introduced cosmetic, detergent, fragrance or topical product on the affected area, unless it is a prescribed medicine that your clinician told you to continue. Rinse off possible irritants, keep the skin cool, wear loose clothing and use a plain moisturiser if it does not sting.

Photograph the rash and record when it started, where it spread, recent products, travel, illness and medicines. Avoid scratching and do not share towels if an infection is possible. Arrange a clinical review when the rash persists, recurs or interferes with sleep.

Seek emergency help for a rash with swelling of the lips or tongue, breathing trouble, faintness or widespread blistering. Get urgent medical advice for fever, severe pain, rapidly spreading redness, skin peeling, purple spots, eye or mouth involvement, or a rash that begins soon after a new medicine.

Ask what features point toward contact dermatitis, eczema, infection or a medicine reaction, whether you should stop a product or medicine, what treatment is safe for the body area, and which changes require urgent review.