Heat rash after sunburn

Sunburn commonly causes tenderness, warmth, redness and sometimes peeling. Heat rash adds small itchy or stinging bumps, often where clothing, straps or skin folds trap sweat. The two problems can overlap, but widespread blistering, marked swelling or intense pain needs a different assessment. Skin redness and skin rash can also have causes unrelated to either condition.

Cool the skin with a lukewarm shower or clean damp cloth; avoid ice directly on the area. Keep clothing loose, leave blisters intact, and do not peel flaking skin. Drink fluids, rest away from heat, and avoid further sun until the skin recovers. Skip fragranced products, harsh exfoliation and thick occlusive creams. A plain moisturiser may help later dryness, while emollient therapy should be chosen with professional guidance for damaged skin.

Seek medical advice for extensive sunburn, repeated vomiting, fever, worsening pain, spreading redness, pus, or skin that is increasingly swollen or hot. Urgent assessment is needed for confusion, fainting, breathing trouble, severe weakness, or blistering that involves a large area. A clinician can check whether the bumps are heat rash, infection, a burn complication or another eruption.

Ask which moisturiser is suitable, how to protect the healing area from sun, and whether any pain or itch treatment is safe for you. If bumps persist after the burn improves, ask whether a topical corticosteroid is appropriate.