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Heat Rash Overview

Heat Rash Causes

Most common in babies, heat rash can affect anyone during hot and humid weather. When people perspire, sometimes their sweat ducts become blocked, and an annoying cluster of pink or red bumps appears on their skin. This is heat rash. It usually affects areas of the skin covered by clothing, where the fabric can become sweaty and rub against the skin. Heat rash is irritating and itchy and can sometimes develop into a more serious infection. However, in most cases, it will heal on its own [source: Peoples-Health].

Heat rash may look like nothing more than a bunch of small, red bumps or pimples. In adults, it usually appears in the folds of the skin, while in babies, it typically develops on the head, neck or shoulders. Heat rash in children tends to occur when parents unintentionally overdress them when the weather is hot. It may seem like children require more protective clothing than adults do, especially on hot summer days, but parents should always dress their children in the same types of clothing they would dress themselves.

Heat rash typically affects babies because their sweat ducts are not developed enough to adequately release perspiration. Adults can develop heat rash during any intense physical activity that causes them to perspire a lot. Certain bacteria on the skin can plug sweat ducts as well, causing irritation. Even some medications, such as diuretics and those used for the treatment of Parkinson's disease, have been found to increase the occurrence of heat rash [source: MedicineNet].

Heat rash will most often disappear on its own after three or four days. Of course, it will be incredibly itchy and annoying during this time. If the heat rash seems to be developing into a more serious infection, contact your doctor.

Possible signs of an infection include:

  • A fever of 100 degrees Fahrenheit (37.8 degrees Celsius) or higher
  • Inflammation of the irritated area
  • The development of pus
  • A swelling of the lymph nodes in the neck, armpit or groin

[source: WebMD]

For the most part, heat rash tends to be more annoying than it is harmful (unless the victim is also developing heat exhaustion -- more on that later). During the long, dog days of summer, it can be practically unavoidable. If you find yourself afflicted, you'll want to know how to treat the symptoms until it has time to heal. Go to the next page to learn about treatments for heat rash.