Heat rash, also called miliaria or prickly heat, is a skin irritation that stings and makes your skin red. If you have heat rash, your skin may feel itchy, small bumps may form, and you may feel some “prickly,” tingling pain.
Heat rash occurs most often in hot, humid weather. If you sweat too much, sweat can get trapped under your skin and block your sweat glands. If your pores cannot clear out the sweat, you may get a rash.
Heat rash is most likely to appear in places where skin touches skin, such as the following:
Heat rash is most common in newborns and infants, but it can also affect adults. It is usually triggered by sweating too much, having a high body temperature, being overdressed or being in a very warm environment. Babies who are bundled in too much clothing and people who are not used to hot weather are most likely to get heat rash.
The most effective treatment for heat rash is to keep your skin cool and dry.
If your rash is severe, your doctor may prescribe a lotion to help relieve your pain or discomfort.
In most cases, heat rash goes away on its own. If your heat rash doesn’t go away after 3 or 4 days, or if it seems to be getting worse, talk to your doctor. In some cases, heat rash may be caused by an infection. See your doctor if your itchiness is severe or if the rash area swells or oozes pus. If you feel dizzy, nauseous, or confused, or you have trouble breathing, go to the emergency room right away. These symptoms can be signs of serious heat-related illnesses, such as heat exhaustion or heatstroke.
In hot weather, dress yourself or your baby in lightweight cotton clothing. Cotton helps absorb moisture to keep it off of your skin.
If the weather is hot, turn on the air conditioner, or use a fan to help you stay cool and dry.
Avoid using baby powders and creams. They can block your pores and actually make your skin warmer.
Written by familydoctor.org editorial staff