What heat rash looks like

Depending on how deeply sweat is trapped, the surface may show fine clear vesicles, small inflamed bumps, or a prickly red patch. It can affect covered areas and skin folds, and itch or stinging may accompany the visible changes. Skin tones can alter how redness appears, so texture, timing after heat, and distribution matter too. The [Heat Rash](/conditions/heat-rash/) page gives broader context; [Skin Bumps](/symptoms/skin-bumps/) and [Skin Redness](/symptoms/skin-redness/) cover related observations.

Notice whether the rash follows sweating, tight clothing, or humid conditions, and whether it improves after cooling. Keep the area clean and dry, wear loose breathable layers, and avoid scrubbing or heavy fragranced products. Take a clear photograph for comparison if the appearance changes, without delaying care when symptoms are severe. A clinician can advise whether [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) is suitable.

Arrange assessment for spreading redness, marked tenderness, warmth, pus, crusting, fever, or blisters that are painful or extensive. Urgent help is needed for breathing difficulty, facial swelling, faintness, or a rapidly evolving rash. If the pattern does not settle with cooling, a clinician can check for infection, eczema, allergy, or another rash and consider [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) when appropriate.

Ask which visual features support heat rash, what changes would suggest another diagnosis, and whether you should show photographs taken before cooling the skin.