Miliaria ("heat rash" or "prickly heat") is an acute itching eruption of the skin that
commonly occurs in hot
summer weather and in
tropical and subtropical areas.
The condition
results from excessive sweating and blocked sweat glands.
Prolonged exposure to heat and moisture causes the skin to swell enough to block the openings of the sweat glands.
Newly produced sweat is then deposited in the skin and not on it; this results in
local irritation and in the formation of minute blisters. Pimples may develop as well as itch due to inflammation, and the involved area may
become infected. Sites that tend to be involved are the chest, back, waistline, groin, and armpits. The best treatment involves
moving the person to a cooler, less humid atmosphere. Lotions, cold compresses, and cool showers or tub soaks also may help. Anything that causes irritation---such as unsuitable clothing, medications, or harsh soaps---should be avoided.
If
fungal infections develop in the affected areas, they
require separate treatment with anti-fungal ointments or other preparations. In cases of
severe itching, antihistamines may be given.