Heat rash, also called prickly heat or miliaria, develops when sweat becomes trapped in blocked sweat ducts. The most effective treatment is usually simple: cool the skin, reduce sweating and avoid further overheating.
What does heat rash look and feel like?
Heat rash often causes clusters of small bumps with itching, prickling or irritation. It commonly affects areas where sweat and friction build up, including the chest, back, neck, under the breasts, groin and skin folds.
How can I prevent heat rash?
- Wear lightweight, loose-fitting clothing.
- Exercise during cooler parts of the day or indoors with air conditioning.
- Use fans, cool showers and air conditioning to reduce overheating.
- Change out of sweaty clothing promptly.
- Reduce friction and occlusion in areas where the rash tends to recur.
How do I treat heat rash at home?
Move to a cool environment, stop activities that cause heavy sweating and keep the affected area cool and dry. Most uncomplicated heat rash improves on its own once sweating is reduced.
What should I avoid?
Avoid heavy occlusive products, tight clothing and repeated overheating while the rash is active. Scratching can worsen irritation and damage the skin.
When should heat rash be checked?
Arrange an evaluation if the rash lasts more than a few days despite cooling, becomes painful, develops pus or spreading redness, or you are not sure whether it is heat rash. Fungal infections, contact dermatitis, folliculitis and other rashes can look similar.
Related: summer fungal infections and when a rash needs evaluation.
Related care: Rash evaluation and treatment · Fungal skin infections · Contact dermatitis