Does sweat rash itch?

What does sweat rash look and feel like?

The usual rash has small raised spots, an itchy or prickly feeling and mild swelling. Some spots contain fluid. The rash often looks red on white skin but can look grey or white, or be harder to see, on brown or black skin. Adults and children often have the same symptoms. Heat rash can appear anywhere and spread across the body, but it cannot pass to another person.2

Why does sweating cause a rash?

Heat rash develops when blocked sweat ducts trap sweat beneath the skin, causing inflammation. It often appears where clothing limits airflow or skin touches skin, such as the armpits, chest, back and inner thighs. Heavy sweating, hot or humid weather and tight clothing make it more likely. Babies are particularly susceptible because their sweat glands and ducts are still developing.1

How can you calm the itch?

1. 1Move somewhere cooler or into an air conditioned room, and remove clothing covering the rash.
2. 2Gently wash the affected skin with cool or lukewarm water. Pat it dry rather than scrubbing.
3. 3Leave the area uncovered where practical, or wear clean, loose clothing that does not rub.
4. 4Apply a cold damp cloth, or an ice pack wrapped in a tea towel, for up to 20 minutes.
5. 5Tap or pat an itchy patch instead of scratching. Avoid perfumed shower gels and creams.

Loose cotton clothing and lightweight bedding help keep skin cool, giving the linen cupboard an unusually useful role in skincare. Keeping cool reduces sweating that irritates the rash.2

Should you put cream on sweat rash?

Avoid layering on lotions, ointments or powders that can block pores and trap sweat. Cooling and airflow are the starting point, rather than giving the bathroom shelf another assignment. If itching is intense, ask a pharmacist about a suitable treatment, such as calamine lotion, antihistamine tablets or hydrocortisone cream. Children under 10 need a doctor's advice before using hydrocortisone for heat rash.12

How long should the itching last?

Heat rash usually improves on its own within a few days. While it heals, limit workouts and other activities that cause heavy sweating. Scratching can delay healing, break the skin and allow infection. If the rash keeps returning, discuss prevention with a healthcare professional, especially if work or the climate makes sweating hard to avoid.12

Itching alone does not identify sweat rash. Dry skin, harsh soaps and reactions to products or medicines can also cause itching. Notice whether symptoms start after bathing or using something new, and mention that pattern if you seek medical advice.3

When should you get medical help?

Get medical advice if the rash does not improve after a few days, becomes painful or intensely itchy, or develops warmth or swelling with fever or chills. Contact a doctor if your baby has a rash that worries you.12

Seek emergency help for an itchy rash accompanied by breathing difficulty, throat tightness, swollen lips or tongue, or collapse. These symptoms can indicate anaphylaxis, a severe allergic reaction requiring immediate treatment, rather than a rash to manage by cooling the skin.4