Heat rash on the bum: practical care

The buttocks can stay warm and damp after exercise, prolonged sitting or close-fitting clothing. Trapped sweat may irritate sweat ducts and cause prickling, itch, small bumps or tiny blisters. Friction can make the skin sore, while creams or wipes that do not suit you can add contact irritation. A rash in this area can also be folliculitis, eczema or infection, so appearance and symptoms matter more than the location alone. See Skin Rash for broader symptom information.

Wash gently after sweating and pat the area completely dry. Change damp underwear promptly and choose loose, breathable clothing. Take breaks from prolonged sitting when possible, and avoid scratching, harsh scrubs, fragranced wipes and thick occlusive products. If the skin is dry rather than moist, a light fragrance-free emollient may limit rubbing; Emollient Therapy explains this approach. Do not use a steroid cream on broken, infected-looking or uncertain skin without medical advice.

Arrange a review if the rash lasts despite cooling and drying, keeps returning, becomes painful, or develops firm lumps or draining spots. Seek prompt medical care for spreading warmth or swelling, pus, fever, red streaks, severe tenderness or rapidly worsening skin breakdown. A painful lump near the anus, or symptoms with bowel changes, should not be assumed to be heat rash.

Could this be heat rash, folliculitis or a fungal problem? Which cleanser or moisturiser is suitable for this area? Should I avoid a particular fabric or product? What symptoms would require same-day care?