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Breaking into a prickly sweat

Prickly heat, or miliaria, can make you miserable. While it usually goes away on its own, there are some things you can do to make the discomfort easier to bear.

Sweat is the best defense your body has against heat. It helps you stay cool. But it can also cause problems.

When it's very hot and humid outside, or when you have a fever, your sweat glands can work so hard that they clog up and become blocked.

This doesn't keep your body from producing sweat. It keeps the sweat from escaping from the pores.

The sweat becomes trapped underneath the skin's surface. The resulting inflammation and tiny red blisters are called miliaria, or prickly heat.

Prickly heat is common in children. Their pores are tiny and clog easily, and some parents swaddle their children in too much clothing, which causes sweating.

Prickly heat can also crop up on just about anyone who wears tight-fitting synthetic clothing or lives in a hot, humid environment.

Luckily, prickly heat usually goes away on its own, without causing scarring or any other long-lasting problem. But it can be quite uncomfortable.

These steps can help relieve the symptoms, according to the American Academy of Family Physicians:

  • Avoid sweating. Even if you stay sweat-free for just a few hours, this should help. If it's hot outside, try to find a place with air-conditioning.
  • Keep your skin free of irritants. Try to dress in loose, cotton clothing that won't rub on the sore spots. Stay away from excessive soaps and other irritants.

And here are some tips for avoiding prickly heat in the first place:

  • Keep the air cool and dry. Use an air conditioner or a fan.
  • Keep the room well ventilated so sweat can evaporate.
  • Dress yourself and your children in loose-fitting, lightweight cotton clothing.
  • Avoid exercising in hot, humid weather.

Reviewed 6/1/2022

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