3 Keys to Recognizing Heat Rash

May 7th 2016

Heat rash is usually nothing to worry about, but recognizing the signs can give you peace of mind. If you develop a rash after spending time in the heat, watch it

Appearance and Sensation

Heat rash tends to appear somewhat suddenly. It takes the form of small, red bumps on the skin. In mild cases, the redness may not be obvious. Instead, these bumps usually appear as tiny blisters. Rubbing them may cause them to break open. In rare cases, the blocked sweat may seep out into the surrounding skin, causing raised bumps that are the same color as the rest of the skin. These bumps typically occur immediately after exercise.

Although mild cases of heat rash may not cause any noticeable discomfort, many people experience itchiness or slight pain. This pain often feels like a mild sunburn.


Heat rash is usually caused when sweat cannot evaporate quickly enough, so it usually appears in areas of skin-on-skin contact, such as the armpits or the backs of your knees. Obese people may notice it in skin folds or other areas where skin rubs against itself, such as the upper thighs and arms. Infants are very susceptible to heat rash and often get it on the backs of their necks.

Clothing or other fabric can also cause heat rash. Tight, heavy clothes, such as tight jeans, are a common culprit. Some people get heat rash during winter if they stay wrapped up in heavy blankets. People with limited mobility may also be more prone to heat rash, since they cannot always move around enough to let sweat evaporate.


Heat rash is usually a very short-lived condition. It should go away within a few hours to a few days as long as you avoid hot, humid conditions and keep your skin cool. Thick lotions, tight clothes and soaps that leave reside can exacerbate the condition, so avoid those while it goes away.

When to Seek Help

Heat rash usually does not need any medical attention, but it can become infected, or you may mistake other conditions for heat rash. Call your doctor if the rash is accompanied by a fever or swollen lymph nodes. Keep an eye on the rash, and seek assistance if the area becomes more inflamed or if you start to feel pain. If it lasts for more than a few days or the rash spreads even though you avoid hot and humid conditions, consider calling your doctor.


Heat rash, sometimes referred to as prickly heat, is a common sight. It often affects infants and young children, but adults can get it too. It occurs when your pores become blocked, usually from excessive sweating or sweat that is unable to evaporate. Heat rash can be uncomfortable, but it is harmless. Find out how to differentiate heat rash from other rashes.

More in category

  • Scabies
    Scabies can form in small patches or red bumps, that may cause itching and rashe...
  • Heat Stroke
    Of the 3 types of heat emergencies: heat cramps, heat exhaustion and heat stroke...
  • 3 Ways to Identify a Fire Ant Bite
    Identify the Insect People who suspect they have been bitten by a fire ant shoul...

Related Content