Prickly Heat

What causes prickly heat?

Prickly heat is thought to be due to blockage of the sweat glands. This can occur when we sweat a lot such as when on holiday in a hot country. Heat, sticky sweat, dead skin cells, and dead bacteria on the skin may all contribute to blocking the sweat glands. If the sweat gland is blocked, the sweat seeps into the nearby skin. This causes tiny pockets of inflammation which causes the rash.

The rash may begin within a few days of arrival in a tropical climate. However, it might develop weeks, or even months, later. Babies and obese people are more prone to prickly heat.

Prickly heat can also occur in cooler climates when sweating is a problem. For example, people who lie on their back for long periods due to illness may get prickly heat on their back.

What are the symptoms of prickly heat?

• Itching - although it may be more of an intense prickling sensation.
• Small, red spots which may look like tiny blisters. Many usually appear all over the body. They occur most where there is friction with clothes.
• Some areas of skin become red.

What is the treatment for prickly heat?

• If possible, avoid excessive heat and humidity.
• Avoid further sweating. Even if this is possible for just a few hours each day it can make a big difference. For example, staying in an air conditioned room for a few hours a day. A cool bath can also be soothing and help to avoid sweating.
• Calamine lotion may cool and soothe the skin.
• Wear loose cotton clothing.
• A steroid cream may soothe the irritation whilst waiting for the condition to clear with the above measures. You can buy hydrocortisone cream, which is a mild steroid cream, from pharmacies.

Prickly heat normally goes in a few days. But, it can sometimes last several weeks if the hot and humid conditions remain.

© EMIS and PIP 2004   Updated: November 2002   CHIQ Accredited