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Prickly heat

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What is prickly heat?

Prickly heat is an allergic reaction to hot temperatures which is often triggered by prolonged exposure to the sun and heat. The main symptom is often referred to as heat rash; an itchy rash formed of small, raised red spots that cause a prickling sensation on the skin.

What causes prickly heat?

Prickly heat is caused by hot or humid weather, as it develops when a person sweats more than usual. As the body’s sweat glands become blocked, trapped sweat causes skin irritation and stinging along with a heat rash. It can develop anywhere on the body but is more often found on the neck, chest and back.

What are the symptoms of prickly heat?

The most common symptoms of heat rash in adults and children are:

  • Small red bumps
  • An itchy, prickly sensation
  • Redness and mild swelling

How to prevent prickly heat

As well as keeping sun safe with a sufficient SPF for your skin, there are ways you can avoid prickly heat and enjoy your summer.

Ways to avoid prickly heat: 

  • Wear loose cotton clothing to keep your skin cool
  • Drink plenty of fluids
  • Invest in lightweight bed linen
  • Take cool baths or showers

How to naturally calm the prickly heat rash

  • Applying a cold flannel to the rash for no more than 20 minutes
  • Patting the rash instead of scratching it
  • Avoiding fragranced products

Although there is no cure for prickly heat, you could speak to your pharmacist about further treatment options such as:

Can you be allergic to the sun?

Yes. Sun allergy (Photosensitivity) occurs when skin is hypersensitive to UV radiation emitted by sunlight. Both UVA and UVB can cause sun allergies resulting in:

  • Skin redness
  • Itching (prickly heat)
  • Inflammation
  • Fluid retention
  • Blisters

Photosensitivity can also spread to areas of the skin not exposed to sun light and may take a few days to appear.

How long does prickly heat last?

Prickly heat rashes last different lengths of time depending on the person and how much sun exposure there has been. If you take precautions to cool down and stay out of the sun, your skin shouldn’t take long to return to normal. If you are concerned it may not be heat rash, especially in babies and children, speak to a medical professional as soon as possible.

Can I take antihistamine tablets for heat rash? 

Some people find antihistamines can help with prickly heat; however some options are not always suitable for everyone. Speak to your pharmacist about which antihistamine tablets might be right for you.