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Sweat rash is a rash developing when the body heats up and perspires, and the rash is usually caused by some minimal to significant blockage of the sweat glands. Many people know this rash by other names like prickly heat, and medically it’s referred to as miliaria. Mild forms of heat or sweat rash are known as miliaria rubra, but severe forms, which are fortunately rare, are called miliaria profunda.
The type of rash that develops with sweat can differ in location on the body. Very often it appears in patches, usually in parts of the body that are cut off from air, like in between skin folds. Areas under the belly, in the underarms and under the breasts are prime possible rash locations. Usually the rash doesn’t spread, and simply looks like a collection of red whiteheads or blisters, but if the person is severely overheated, the rash could be present on a significant part of the body or in several different large patches.
The reason that sweat rash gets the name prickly heat is because the rash can sting or prickle. Others note it is very itchy and uncomfortable for its duration. The good news for most people is that the rash often resolves in just a couple of days. Treatments recommended could be to wear cool clothing, bathe and pat dry the rash areas, and use a water-based anti-itch cream, if needed. Others find benefit from baby powder or cornstarch to reduce perspiration.
Most suggest that it’s seldom necessary to see a doctor unless the rash is profuse or if the blistering portions of it break open and form scabs on the skin. The latter may be an infection or it could be chickenpox, especially if the rash is not confined to a single area but occurs in spots instead of patches. Any time the rash appears infected, a doctor should be consulted to avoid potential blood infection or cellulitis.
It can be hard to avoid sweat rash, and some people seem more prone than others to getting it. Those in humid areas tend to get it most because these areas cause more perspiration. It doesn’t necessarily have to be hot for the rash to occur, and some people will develop the condition by exercising and perspiring significantly, or if they get a very high fever. Those trying to avoid the rash are advised to use air conditioning, dress for the weather, and employ things like showers to cool down.
A very severe version of this rash called miliaria profunda is usually not best treated at home. This rash may be spread over a larger part of the body, and be white in color instead of the bumpy red of prickly heat. It doesn’t prickle or sting, but instead burns. Due to the great discomfort this more serious form of sweat rash creates, getting medical attention if it occurs is advised.