When to see a doctor. Some soothe your skin or cool it down, while others reduce Best heat rash treatment adults and itching while preventing infection. Healthline and our partners may receive a portion of revenues if you make a purchase using a link above. This may lead to an inability to sweat in response to heat. It happens when a blockage of the sweat glands causes perspiration to be caught in the deeper layers of the skin. It often goes away on its own in cool temperatures.