What causes heat rash?

Heat rash, also known as prickly heat or miliaria, is primarily caused by the blockage of sweat glands when the body overheats. This blockage can occur due to various reasons, with the primary cause being poor hygiene and clogged pores. When sweat is unable to escape through the pores, it can accumulate and irritate the skin, leading to inflammation and a rash.

While excessive sweating during exercise can contribute to heat rash, it is the failure of sweat to exit through the pores, often exacerbated by factors such as inadequate hygiene, that is the underlying cause. Similarly, sun exposure without sunscreen can lead to sunburn and skin irritation, but it does not directly cause the secretion blockages responsible for heat rash. Dehydration in high temperatures can lead to other heat-related illnesses but, like sun exposure, is not a primary contributor to the condition. Hence, the choice that points toward poor hygiene and clogged pores accurately identifies the primary mechanism behind heat rash.