What should you know about heat rash red bumps?

Heat rash, also called prickly heat or miliaria, develops when sweat cannot move freely to the skin surface. Red bumps may feel prickly, itchy, or tender, especially beneath tight clothing or in skin folds. The pattern often matches areas that become hot and damp, such as the neck, chest, back, groin, or underarms. Red bumps can also occur with other forms of skin rash, so their appearance alone cannot confirm the cause.

Review the related information on [Heat Rash](/conditions/heat-rash/) and [Skin Bumps](/symptoms/skin-bumps/) if you need help comparing patterns.

Move into a cooler environment and let the affected area dry. Wear loose, breathable clothing and change out of sweaty garments promptly. A cool, damp cloth can soothe prickling; pat the skin dry instead of rubbing it. Avoid heavy oils, greasy ointments, fragranced products, and vigorous scrubbing because they can hold heat or irritate blocked ducts.

A bland moisturizer may help if the surface is dry; see [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) for general guidance. Do not start a medicated cream on broken or infected-looking skin without professional advice.

Arrange an assessment if the rash is spreading, repeatedly returning, very painful, or not improving after cooling and reducing sweating. Seek prompt care for increasing warmth, swelling, pus, fever, marked tenderness, or red streaking, which can signal infection or another diagnosis. Breathing difficulty, facial swelling, faintness, or a rapidly widespread rash needs urgent medical attention.

Ask whether the distribution fits heat rash, whether another rash could explain the bumps, and which skin products are suitable for the area. If inflammation is substantial, ask whether [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) are appropriate and how to use them safely.