Don't sweat it
Key takeaways:
- Heat rash can happen after you've spent time in a hot or humid setting. It looks like red bumps or blisters.
- Most cases resolve on their own after you get to a cool space, shed clothing and wipe off sweat. If your symptoms get worse, see a health care provider.
- Don't pop or itch the blisters. Don't use rubbing alcohol or peroxide on the rash.
Summer may be winding down, but health care providers want you to know that heat rash can happen year-round. Luckily, most cases resolve on their own with simple steps.
Maddy Draper, APRN, a provider at OSF OnCall, says heat rash (also called sweat rash or prickly heat) usually occurs in a hot or humid setting. This could be the summer heat or a year-round activity like the sauna or gym. Or, Draper says, using certain things on your skin – like bandages, medicine patches or thick lotion – can contribute. Either way, the result is clogged ducts trapping sweat under the skin, leading to a rash.
“It’s either raised, red bumps or blisters filled with clear fluid or pus,” Draper explains.
Draper adds that heat rash is more common in infants and young kids, but it can affect all ages. She says providers typically see the rash on a person’s midsection – front and back. It can also crop up on your arms and legs, especially where patches of skin come together, like your armpit. Sometimes the rash will be itchy.
“There’s no cure for it. It’s just getting back into a normal, less hot environment. Wear less clothing. Get the sweat off your body,” Draper says.
Don’t pop the blisters, as that can lead to a bacterial infection. Don’t use rubbing alcohol or peroxide on the rash, and don’t scratch the itch.
In other words: “Just leave it alone,” Draper says, and most cases will resolve in a few hours.
When to see a health care provider? If you develop a fever, if the rash persists for a couple days or if it looks different (such as red streaks up your arm), visit your local urgent care. In rare cases, blocked ducts can cause sweat glands to stop working. That makes it harder for the body to cool itself, and you can be prone to overheating.
Heat rash prevention involves many of the “hot environment” safety tips you’ve heard before.
“Stay in cooler environments,” Draper advises. “Everyone likes to be outside in the warmth, but try not to prolong those exposures. If you feel symptoms [of heat illness], come inside and cool off.”
During those breaks, drink water or a sports drink, wipe off sweat and change out of damp clothes. Also, remove bandages or patches when doing something that makes you sweat.