As the UK experiences its third heatwave of the year, with amber heat health alerts across large parts of England, many people are dealing with heat rash, also known as prickly heat.
Searches for “how to prevent heat rash” have risen by 300% over the past 30 days, while searches for “how to get rid of prickly heat fast” have increased by 200% as people look for ways to relieve irritated skin.
To help, Cult Beauty spoke with dermatologist Dr Sweta Rai, who explained what causes prickly heat and how to treat and prevent it.
What is prickly heat?
Heat rash appears as small, red, pinhead-sized spots on exposed areas of the skin. Unlike allergy flare-ups, it is not caused by histamine, so antihistamines will not help.
The condition, medically known as miliaria, develops when blocked sweat ducts trap perspiration beneath the skin during hot and humid weather. It is more likely to occur when sweating increases but cannot evaporate because of clothing or environmental conditions.
How to soothe prickly heat
Dr Rai recommends the following steps to calm a flare-up
- Store skincare products in the fridge for an instant cooling effect.
- Apply cool compresses to reduce irritation and inflammation.
- Switch to lightweight, non-comedogenic skincare products.
- Take cool showers instead of long, hot ones.
- Wear loose, breathable clothing, particularly natural fibres such as cotton.
“Keeping your temperature and your skin as cool as possible is key,” says Dr Rai.
Medical experts also recommend keeping the affected area cool and dry by minimising further sweating. Symptoms usually improve within a few days once the trigger is removed.
How to prevent it
Dr Rai advises the following steps to reduce the risk of prickly heat
- Check the weather forecast and adjust your routine on hotter days.
- Stay in cool or shaded places during the hottest part of the day.
- Choose loose, breathable clothing instead of tight or synthetic fabrics.
- Avoid overheating and excessive sweating where possible.
Additional advice from health experts includes maintaining good hygiene without using heavy creams, exfoliating gently, and keeping skin folds dry, particularly during humid weather.
The current heatwave has brought temperatures into the mid-30°C across parts of southern and eastern England. Amber alerts issued by the UK Health Security Agency warn of increased risks to health services and vulnerable people during the period of sustained hot weather.
Prickly heat can affect anyone, although it is often more noticeable where skin rubs together or clothing traps moisture. The condition is usually mild, but persistent cases or those showing signs of infection should be assessed by a healthcare professional.
Dr Rai, a consultant dermatologist at King’s College Hospital in London, says practical measures to keep the body cool and reduce sweating are the most effective way to manage and prevent prickly heat. Her recommendations are consistent with established medical guidance on treating miliaria.