A prickly heat rash is initiated by exposure to hot temperatures and humid conditions that lead to excessive sweating and blockage or inflammation of the skin sweat ducts. This causes sweat to be trapped under the skin and this in turn irritates the skin causing a prickly skin rash to develop.
A prickly heat skin rash, characterized by tiny red spots on the skin, is known by several other terms such as: prickly heat, heat rash, and miliaria. It is a little different than a sweat rash which involves fungal activity on the skin, but often sweat rash is also used to describe this type of skin rash.
The rash that develops is rather painful and uncomfortable. It is red and is itchy and prickly or in other words the rash produces a stinging type sensation. It occurs most often in covered skin areas that tend to sweat more such as under the breasts, the groin area, armpits, etc. This type of skin rash can affect any person in any age group, but because the sweat glands of children are not fully developed, they tend to experience the prickly heat skin rash more often that adults.
Miliaria heat rash can be classified into different categories depending on the extent to which the sweat glands are blocked. Miliaria rubra is the most common and occurs when sweat leaks into the deeper layers of the epidermis. Miliaria crystalline is a mild form of the heat rash and produces only small tiny blister like pimples with no intense itching or stinging. Miliaria profunda occurs when the sweat gland obstruction is much deeper in the skin matrix and causes more intense symptoms than miliaria rubra.
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