Emergency advice

Heat rash:

  1. Drink water.
  2. Have a cold bath/shower.
  3. Apply ice pack.
  4. Wear loose cotton clothing.
  5. Avoid excessive heat.
  6. Seek advice if worried.

What is heat rash?

Heat rash consists of small red spots or raised bumps that can cause a stinging or prickling feeling on the skin, sometimes called prickly heat. It occurs when sweat glands are blocked due to the casualty sweating more than normal. It can appear anywhere on the body, but usually appears on the face, chest, back and thighs.

Signs and symptoms

Someone with heat rash may have:

  • a rash of tiny red spots, blisters or bumps   
  • a prickling or burning feeling on their skin
  • itchy skin
  • redness and mild swelling.

What to do

If they have these symptoms, the rash is not serious and should go in a few days.

  1. Tell them to drink lots of water to prevent them becoming dehydrated.

  2. Take a cool bath or shower to cool the skin and prevent further sweating.

    • Do not use perfumed shower gels or creams as this could irritate the skin.
  3. Apply a cold ice pack wrapped in a tea towel for up to 10 minutes.

  4. Wear lose clothing, preferably made of cotton, which will not trap the heat as much as synthetic fibres.

  5. Suggest they avoid excessive heat such as a fire, heater or sitting in the sun, to prevent aggravating the rash.

  6. Advise them to see a pharmacist or healthcare professional for further treatment if required.

    • They may prescribe calamine lotion, an antihistamine or low strength hydrocortisone cream.
  7. If they are concerned or unwell, seek medical advice.

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