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What’s the Best Way to Treat Heat Rash?

Although heat rash often associated with infants, it can affect anyone. What are the best treatments for it and how can you prevent it in the first place?
What's the Best Way to Treat Heat Rash?
By Dave Walker, RPh
Published: August 8, 2018
Last updated: August 9, 2018
 

Question: It’s summer and I’m going to be spending a lot of times outdoors. I’m susceptible to heat rash. What is the best treatment for it?

I remember anticipating summer vacation as a kid. We were always busy planning and participating in neighborhood sporting activities, biking, hiking, fishing and camping trips. The neighborhood moms always had a ready supply of Band-Aids, Bactine and antiseptic cream to take care of those expected and inevitable scratches, scrapes, cuts and insect bites along the way.

But I also remember a couple of occasions when I developed an itchy, stinging rash on my back, abdomen and upper legs. My mother called it prickly heat or heat rash. It seemed to happen unexpectedly in hot weather. Mowing the lawn in 95 degree weather or traveling in the back seat of a car with clear plastic seat covers and no air conditioning seemed to be some of the causes for me.

Heat rash is a term used to describe several skin conditions that are brought on by heat exposure or overheating. Also known as prickly heat, sweat rash or miliaria, it can affect anyone. Infants tend to be more susceptible to heat rash possibly due to the fact a newborn’s sweat ducts are not fully developed. Adults who are bedridden or have larger skin fold areas in the groin, under the arm or under breasts may also be more susceptible. It’s more prevalent in hot, humid climates but can occur anytime the body is overheated or during periods of intense physical activity, whether exercise or work-related.

Heat rash occurs when blocked pores or sweat ducts trap perspiration under the skin causing inflammation with an itching or stinging sensation. The salty sweat trapped under the skin causes the irritation which can lead to small blisters or red bumps that may become quite inflamed and possibly infected. Most cases of mild heat rash clear up in a few days but you should seek medical attention if it gets worse or lasts more than a week.

The first treatment I recommend is washing the area with cool water and a mild soap. Allow the skin to air dry and avoid rubbing with a towel. Try to remain in an air-conditioned environment to allow the skin to cool off. A cool compress like a washcloth may be used intermittently for 15-20 minutes each hour but remember to allow skin to air dry between applications. You want to avoid skin-to-skin contact by placing a clean, dry cotton washcloth or other breathable material under the breasts or between skin folds on the abdomen, under arms or buttocks.

For mild cases, I recommend using calamine lotion to help control itching. A cool, colloidal oatmeal (ground oatmeal suspended in a liquid, usually water) bath like Aveeno seems to help, especially in children. Some people get relief using prickly heat or similar type of powder. For more severe symptoms, you might need to use an over-the-counter topical hydrocortisone cream or mild prescription corticosteroid like triamcinolone cream. Taking an oral antihistamine like Benadryl (diphenhydramine) may help with the itching and, because it causes drowsiness, may help you get a better night’s sleep.

Although heat rash is unpredictable, heat rash symptoms may be preventable or reduced. You can dress in loose, lightweight cotton clothing that breathes. Avoid wearing synthetic fabrics like acrylic, polyester or rayon which hold moisture close to the skin. Drinking plenty of water to remain hydrated helps to keep your body cool. Keep your body cool by spending time in air-conditioned environments. Be creative in finding ways to stay cool this summer.

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Dave Walker, RPh
Dave Walker, RPh

Dave Walker, RPh, is a pharmacist and a member of the MedShadow medical advisory board. He has practiced in multiple pharmacy settings as a pharmacy owner, hospital director of pharmacy, district manager for a pharmacy staffing agency, and currently director of pharmacy at a rural, nonprofit clinic and pharmacy. You can follow him on Twitter @drwalker_rph.