Heat rash

Overview

Common in babies and hot weather.

Heat rash is very common in babies and in hot, humid weather.

It usually clears once the skin cools and dries.

Symptoms

Common signs:

• Tiny itchy bumps in hot weather

Less common

• Prickly or stinging feeling
• Clear tiny blisters
• Rash in skin folds

Look up a symptom: Itching · Tiny itchy bumps in hot weather

When to get medical care

Causes

Heat and sweat.

Does it spread or run in families?

• It isn't contagious. You can't catch it from someone else.

Who is more likely to get it

• Babies

Possible complications

• Heat exhaustion

Diagnosis

Usually no tests.

Treatment

Cool the skin.

Self-care

• Move to a cool place
• Wear loose cotton
• Take a cool shower
• Avoid heavy creams that block sweat glands
• Let skin air-dry after sweating

Prevention

To lower your risk or prevent problems:

• Keep cool in hot weather
• Dress babies lightly
• Use fans

Which doctor treats this

• Start with your primary care provider (family doctor or internist).
• They may send you to a dermatologist (skin doctor).

Back to school, work, or sports

• Most people keep up normal school and work. Rest when you need to.

Children, pregnancy, and older adults

• Babies: Very common; avoid overbundling.
• Adults: Common with exercise in heat.

Pregnancy and breastfeeding

• If you're pregnant or planning to be, tell your prenatal provider about this condition.
• Some skin medicines, like isotretinoin and retinoid creams, aren't safe in pregnancy.
• Don't start or stop any medicine on your own. Some are safe in pregnancy and some need to be changed.
• Ask before taking any pain reliever. The FDA advises avoiding ibuprofen and naproxen after 20 weeks unless your doctor says to.
• Breastfeeding: Most medicines are fine, but ask. The NIH LactMed database lists what's known about each one.

Outlook

Clears.

Clears in days once the skin cools.

Getting ready for your visit

Bring a list of your symptoms and medicines.

Questions to ask

• Is this heat rash or something else?

Research studies

Research studies test new ways to find and treat health problems. Some are looking for volunteers. Talk with your doctor before joining one.

Search ClinicalTrials.gov for studies on Heat rash