What typically causes miliaria rubra?

Miliaria rubra, commonly known as heat rash or prickly heat, is primarily caused by excessive heat exposure. This condition occurs when sweat glands become blocked, leading to the accumulation of sweat beneath the skin. Under warm and humid conditions, the body's ability to cool itself through sweat is compromised, which can lead to irritation and inflammation of the skin.

When the sweat does not evaporate properly, it can cause red, itchy bumps and a prickling sensation on the skin, indicative of miliaria rubra. Recognizing that this condition is directly linked to thermal stress rather than an allergic response or infection helps in understanding the proper management and prevention strategies, such as keeping the skin cool and dry.