How to manage a sun rash

A rash after being outdoors may be a reaction to ultraviolet light, heat, sweat, a product exposed to sunlight, or a medicine that increases light sensitivity. It can cause itchy bumps, redness, burning, swelling, or small blisters on exposed areas. The timing and distribution matter: a rash limited to covered skin may point toward friction or heat, while a rash with scaling, rings, or intense night-time itch may have another cause. Sun exposure can also aggravate atopic dermatitis or psoriasis.

Move into shade, cool the skin with a damp cloth, wear loose clothing, and avoid scratching. Pause newly introduced fragrances, cosmetics, or topical products until the cause is clearer. Use sun-protective clothing and seek advice from a pharmacist or clinician before applying a medicated cream, particularly if the skin is blistered or the rash is widespread. Keep a note of medicines, products, and the timing of sun exposure.

Get urgent help for trouble breathing, facial or tongue swelling, faintness, extensive blistering, severe skin pain, confusion, or signs of serious sunburn. Arrange a medical review when the rash keeps returning, spreads beyond exposed skin, develops pus or fever, or does not improve after leaving the sun.

Ask whether the pattern fits a light reaction, heat rash, contact dermatitis, or another condition; whether a medicine could be involved; and which sunscreen or treatment is suitable for your skin.