Heat rash, also called prickly heat or miliaria, is a common condition in which areas of the skin feel prickly or sting due to overheating. Blocked sweat glands cause this. Because the sweat cannot get out, it builds up under your skin, causing a rash and tiny, itchy bumps. When the bumps burst and release sweat, many people feel a prickly sensation on their skin. It can itch a lot, but it’s not dangerous.

Heat rash looks like tiny bumps surrounded by red skin. It usually happens on clothed parts of the body, such as your back, abdomen, neck, upper chest, groin, or armpits. And it usually gets better once your skin cools off.

Heat rash happens most often in hot, humid conditions. It’s most common in infants. Active people, newborns in incubators, and people on bed rest with fever also are more likely to get it.

You can get a heat rash when you sweat too much. The ducts from the sweat glands in your skin become blocked. This causes the sweat to leak into the surrounding tissue, which leads to irritation and redness. You may feel the prickly, or stinging, sensation that gives this condition its name.

Symptoms of Heat Rash
  • The rash may feel prickly, stinging, or burning.
  • The rash is severe or painful or does not go away on its own within a few days.
  • You develop an infection in an area where you recently had heat rash.
  • You have a fever or any other signs of illness.
  • The rash is bright red or has streaks.
  • The rash starts after you have been taking an antibiotic or new medication.
Treatment and Prevention

  • Move to a cooler, less humid place.
  • Don’t scratch your skin, or it could become infected.
  • Keep the affected area dry.
  • Don’t use ointments or creams that keep your skin moist.
  • You can put powder on the rash to feel more comfortable.
  • Keep your skin cool by using fans, cool showers, and air-conditioning.
  • Wear clothes that aren’t tight and don’t trap heat and moisture.

While these summer skin problems can dampen your fun, they’re usually not serious. Most go away in a few days to a few weeks. If a rash or other skin problem lingers or worsens, you should call your dermatologist’s office.