What should you know about heat rash scab?

Heat rash usually causes prickling, itch, redness, or small bumps rather than a true scab. A crust can form after scratching breaks the surface, after a spot leaks fluid, or when a separate infection or skin condition is present. A scab therefore deserves closer attention, particularly if it is yellow, moist, painful, surrounded by spreading redness, or repeatedly reopening.

Read about [Heat Rash](/conditions/heat-rash/) and [Skin Rash](/symptoms/skin-rash/) while noting how the area has changed.

Do not pick or peel the scab. Clean gently with water and a mild cleanser, pat dry, and reduce heat, sweat, and rubbing. Keep clothing loose and avoid applying fragranced, harsh, or heavy products over broken skin. If the surface is dry around the scab, ask a clinician or pharmacist whether [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) is suitable; do not place an unadvised steroid cream on an open or infected-looking area.

Arrange medical care if the scab is enlarging, painful, warm, swollen, draining pus, or accompanied by fever. Seek advice if new spots keep appearing or the area does not heal after scratching stops. Urgent help is appropriate for rapidly spreading redness, severe illness, facial swelling, breathing difficulty, or faintness.

Ask whether the crust is from scratching, infection, or another rash; whether it needs a swab or specific dressing; and which products are safe on nearby skin. Ask before using [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) because broken skin can change treatment choices.