Multiple small, raised, itchy spots that appear on the skin in hot conditions
Prickly heat is an intensely itchy rash that most commonly occurs in hot weather. It develops when sweat glands are blocked by bacteria and dead skin cells. Sweat trapped in the glands then causes mild inflammation. The rash consists of tiny, red, itchy spots or blisters accompanied by a prickling or burning feeling. The most common sites are the hands, feet, armpits, and chest. Prickly heat is more likely to affect overweight people because they tend to become overheated and sweat easily. Infants and children are more likely than adults to have the condition, in which case the rash develops in the nappy area or on the face, chest, or back.
The rash often disappears on its own in a few days. You can help this process by wearing loose clothing made from natural fibres and, in babies, by leaving nappies off as much as possible. If the rash persists, your doctor may suggest using a mild topical corticosteroid, but this should not be used on the face. Consult a doctor before using a topical corticosteroid on a baby and always follow the doctor’s instructions.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.