What causes prickly heat?
Prickly heat usually develops when a person sweats more than usual, such as during hot or humid weather. However, it is also possible to get prickly heat in the winter.
The condition is caused when the body's sweat glands become blocked. Excessive sweating can result in sweat becoming trapped beneath your skin. The trapped sweat causes skin irritation and the characteristic heat rash.
The symptoms of prickly heat are usually worse in areas that are covered by clothing. This is because clothing can make you sweat and sometimes causes friction (rubbing).