Is this your child's symptom?
- A fine pink rash caused by overheating
- Mainly on the neck, chest, and upper back
Symptoms of Heat Rash
- Tiny, pink bumps
- Mainly on the neck, chest and upper back
- Occurs during hot, humid weather or after lots of sun
- Heat rash can be itchy
- Older children may have a "prickly" pins and needles feeling
- In babies, the rash can have some tiny water blisters
- No fever or illness
- Also called "prickly heat"
Causes of Heat Rash
- Heat rash is caused by blocked-off sweat glands.
- Hot Weather. Hot, humid weather can cause the sweat glands to be overworked.
- Ointment. Babies can also get it in the wintertime from ointments put on the skin. Reason: Ointments can block off sweat glands.
- Location. Heat rash of the forehead can be caused by oil or ointment on the hair. Heat rash of the face of a breastfed baby can be caused by lanolin put on the nipples. Heat rash of the chest can be caused by menthol ointments put on for coughs.
- Exercise. Older children can get heat rash with hard exercise.
When to Call for Heat Rash
Call Doctor or Seek Care Now
- Fever and looks infected (spreading redness or pus)
- Your child looks or acts very sick
- You think your child needs to be seen, and the problem is urgent
Contact Doctor Within 24 Hours
- Looks infected (spreading redness, pus), but no fever
- You think your child needs to be seen, but the problem is not urgent
Contact Doctor During Office Hours
- Rash is not gone after 3 days of treatment
- You have other questions or concerns
Self Care at Home
Seattle Children's Urgent Care Locations
If your child’s illness or injury is life-threatening, call 911.
Care Advice for Heat Rash
- What You Should Know About Heat Rash:
- Heat rash is caused by blocked-off sweat glands.
- It's common in hot, humid weather.
- Here is some care advice that should help.
- Cooling the Skin:
- Cool off the skin to treat and prevent heat rash.
- For large rashes, give your child a cool bath without soap. Do this for 10 minutes. (Caution: Avoid any chill.) Let the skin air-dry. Do this 3 or more times a day.
- For small rashes, put a cool, wet washcloth on the area. Do this for 5 to 10 minutes. Then let the skin air-dry.
- Dress in as few layers of clothing as you can.
- Lower the temperature in your home if you can.
- Sleeping Cooler:
- When your child is asleep, run a fan in the bedroom.
- During sleep, have your child lie on a cotton towel to absorb sweat. (Note: Only for older children age over 1 year.)
- Steroid Cream for Itching:
- Use 1% hydrocortisone cream (such as Cortaid). No prescription is needed.
- Put it on itchy spots 3 times per day.
- Avoid hydrocortisone ointment.
- Calamine lotion can also work.
- Do Not Use Ointments:
- Avoid all ointments or oils on the skin. Reason: They can block off sweat glands.
- Be sure the rash isn't caused by a menthol ointment being used for a cough.
- What to Expect:
- With treatment, heat rash will clear up in 2 to 3 days.
- Call Your Doctor If:
- Rash lasts more than 3 days on this treatment
- Rash starts to look infected
- You think your child needs to be seen
- Your child becomes worse
And remember, contact your doctor if your child develops any of the 'Call Your Doctor' symptoms.
Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.
Last Reviewed: 10/11/2023
Last Revised: 12/30/2022
Copyright 2000-2023. Schmitt Pediatric Guidelines LLC.
FAQs
Polymorphic light eruption can be easily mistaken for heat rash (prickly heat). Prickly heat is caused by warm weather or overheating, rather than sunlight or UV light.
What happens if you ignore heat rash? ›
Heat rash (prickly heat) is uncomfortable but usually harmless. It should clear up on its own after a few days. See your GP if the rash doesn't improve after a few days or your baby has a rash and you're worried.
What does a mild case of heat rash look like? ›
Miliaria rubra (A), one type of heat rash, appears as clusters of small, inflamed blister-like bumps that can produce intense itching. Miliaria crystallina (B), another type of heat rash, appears as clear, fluid-filled bumps that don't hurt or itch. Heat rash usually goes away once the skin cools down.
What cream is best for heat rash? ›
The best creams for heat rash are calamine lotion and corticosteroid cream. One common type of corticosteroid cream is 1% hydrocortisone cream (this is different from hydrocortisone ointment, which can clog sweat glands). Talk to a doctor before using hydrocortisone cream for children under 10 or if you are pregnant.
Should I moisturize a heat rash? ›
It may help to let your skin air-dry. Avoid using oily or greasy moisturizers, cosmetics, sunscreens and other products that can block pores further. Instead use a moisturizer with wool fat (anhydrous lanolin), which helps prevent sweat ducts from getting clogged.
Why do I suddenly have heat rash? ›
Heat rash happens when your sweat glands become blocked. Heat rash can cause red spots or clear blisters that are itchy. Heat rash is common in babies, and in people who are adjusting to warmer temperatures. You can talk to your doctor about medications to help ease heat rash symptoms.
How many days does a heat rash last? ›
Once you start cooling your body down, a mild heat rash could go away within a day. On average, heat rashes last two to three days. More severe heat rashes can last up to a couple of weeks without treatment.
Why isn't my heat rash going away? ›
They go away by themselves. If your rash doesn't go away after 3 or 4 days, or if it seems to be getting worse, call your doctor. In some cases, the rash may be caused by an infection. See your doctor if your itchiness is severe or if the rash area swells or oozes pus.
Is vaseline good for heat rash? ›
Ointments or Vaseline – Antibiotic ointments like Neosporin or ointments that contain mineral oil or petroleum (such as Vaseline) can clog your pores and make your heat rash worse. Scented lotions, perfumes, or creams – Scents and fragrances can irritate sensitive skin even further, as can heavy creams.
What is the difference between a heat rash and a sun rash? ›
Similar to sunburn, a heat rash, also known as 'prickly heat' or miliaria, is a red rash on the skin. But unlike sunburn, heat rash can cause small, itchy, fluid-filled bumps on the skin, and it can be skin that was never even exposed to sunlight.
Taking an over-the-counter (OTC) antihistamine tablet can help to relieve the itching and any swelling of heat rash. Oral antihistamines, such as hydroxyzine and diphenhydramine, can help to relieve itching. Some types can cause drowsiness, so it may be best to use them at night.
How long does it take a heat rash to go away? ›
How long does it take to get rid of a heat rash? Once you start cooling your body down, a mild heat rash could go away within a day. On average, heat rashes last two to three days. More severe heat rashes can last up to a couple of weeks without treatment.
Does Benadryl help a heat rash? ›
Heat rash can be itchy, but avoid the urge to scratch. Scratching irritated and damaged skin can lead to skin infections. You can try taking an over-the-counter (OTC) antihistamine to combat that itchy feeling, such as: Diphenhydramine (Benadryl)
Can Vaseline remove heat rash? ›
Ointments or Vaseline – Antibiotic ointments like Neosporin or ointments that contain mineral oil or petroleum (such as Vaseline) can clog your pores and make your heat rash worse. Scented lotions, perfumes, or creams – Scents and fragrances can irritate sensitive skin even further, as can heavy creams.