Heat rash, also known as prickly heat, sweat rash and miliaria, is an itchy, red skin rash that often causes a mordant or prickling sensation. It is common in infants but can affect adults too, especially during hot, humid weather. Heat rash develops when sweat ducts become blocked and perspiration is trapped under the skin. This causes irritation and results in the rash. It is common in a hot or humid climate, though it can also occur in winter. affection range from shallow blisters to deep, red lumps. Some forms of heat rash can trigger an intensely itchy or prickly feeling...
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