Treatment for an itchy sun rash

A rash after sun exposure may be driven by heat and sweat, direct irritation, a reaction to a product, or sensitivity triggered by light. Heat Rash often affects covered or sweaty areas. Contact Dermatitis may follow sunscreen, fragrance or plant exposure. Atopic Dermatitis and Psoriasis can flare when the skin barrier is stressed. A Drug Rash can be light-sensitive, and Ringworm or Scabies may be coincidental rather than caused by the sun.

Move into shade or an air-conditioned space, take a cool shower or use a cool damp cloth, and wear loose, breathable clothing. Apply a bland, fragrance-free moisturiser after cooling the skin. Avoid scratching, exfoliating, fragranced products and further direct sun until the skin settles. Review any new medicines, supplements, sunscreen or cosmetics with a clinician or pharmacist; do not stop a prescribed medicine without advice. Keep irritated skin clean and dry, especially in folds.

Seek urgent care for trouble breathing, swelling of the lips or face, faintness, blistering over a large area, severe pain, fever, confusion or signs of dehydration. Arrange a medical review if the rash spreads, recurs after sun, involves the eyes or mouth, develops pus, or does not improve after avoiding heat and suspected triggers. A rash in a skin fold with moisture and soreness may need specific treatment.

Could this be Heat Rash, Contact Dermatitis, a Drug Rash or a light-sensitive flare of another condition? Which moisturiser or anti-itch treatment is suitable? Should I change sunscreen, review medicines or test for infection?