Heat rash (prickly heat)

Heat rash is uncomfortable, but usually harmless. It usually gets better on its own after a few days.

Check if you have heat rash

The symptoms of heat rash are:

The rash often looks red, but this may be less obvious on brown or black skin.

The symptoms of heat rash are often the same in adults and children.

It can appear anywhere on the body and spread, but it cannot be passed on to other people.

A red, patchy rash with some small, raised bumps, on the side of a child's chest. Shown on white skin
Heat rash appears as raised spots that are 2mm to 4mm across. Some spots may be filled with fluid.

If you're not sure if your child has heat rash

Look at other rashes in children.

How you can treat or prevent heat rash yourself

To keep your skin cool

The main thing to do is keep your skin cool so you do not sweat and irritate the rash.

To calm the itching or prickly feeling

A pharmacist can help with heat rash

Speak to a pharmacist about heat rash. They can give advice and suggest the best treatment to use.

A pharmacist might recommend:

Non-urgent advice: See a GP if:

  • the rash does not improve after a few days
  • your baby has a rash and you're worried

Causes of heat rash

Heat rash is usually caused by excessive sweating.

Sweat glands get blocked and the trapped sweat leads to a rash developing a few days later.

Babies often get heat rash because they cannot control their temperature as well as adults and children can.

Page last reviewed: 15 February 2021
Next review due: 15 February 2024