heat rash on the backby James Hubbard, M.D., M.P.H.

Believe it or not, I grew up in Mississippi and didn’t know what prickly heat was until I started my practice. In medical training we didn’t concern ourselves with such trivialities. But in real life prickly heat, or a heat rash, can be quite an itchy, prickly nuisance. Many people came to see me for this, and I learned how to recognize it pretty fast. And the heat-rash remedies? They haven’t really changed in those thirty years.

So why, in a survival medicine blog, should I even bring it up? Because in summer disaster situations, with less bathing and no air-conditioning, heat rashes are bound to be more common, and more likely to become serious skin infections. They can even make you more prone to heatstroke. Here’s why.

What’s So Dangerous About a Heat Rash?

A heat rash consists of clogged-up sweat glands. The glands continue to try to sweat when appropriate, but the sweat is trapped. Trapped sweat irritates the skin and causes the bumps.

During a disaster, if you scratch and don’t keep it clean, it can get infected. Also, clogged-up sweat glands means you don’t have as much sweat to evaporate and cool off your skin. Hence, your body can’t cool as well, and your risk of heat stroke rises.

Oh, by the way. Heat rashes are more common in children because, like the rest of them, their sweat glands have not fully developed and are easier to damage and clog.

How Do You Recognize a Heat Rash?

After being exposed to the heat, you notice a rash with tiny red, yellow, or skin-colored, pinpoint-size bumps that may contain small bits of sweat. They usually occur more on the face, neck, and trunk than on the extremities.

If on the extremities, the bumps are going to be around the armpits, inner elbows, back of the knees, or groin. They could also occur in an area that got hotter that the rest of the body, as from sitting, or from clothes.

What Are the Heat-Rash Remedies?

1. You must keep the skin cool.

  • Rubbing ice on the rash for a few minutes can help.
  • Also keep the rash area open to the air, or
  • Wear loose, cotton clothes so your skin can cool and the sweat evaporate.

2. Try to gently unclog the pores.

  • Take frequent showers or baths, but to avoid irritating the skin more, don’t scrub hard, and use a mild soap.
  • Lanolin can help unplug the pores.
  • Avoid thick ointments, creams, and oils since they could clog more pores. Except …

3. Over-the-counter steroid creams can ease the irritation and itching.

What Are the Warning Signs of Infection?

  • Fever
  • Red streaks
  • Pus in a bump
  • Tender, swollen lymph nodes in the neck, armpits, or groin

With infection the treatment remains the same except you’ll need an antibiotic.

What’s been your experience with heat rashes and home remedies?

Photo by Ian Terry.