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Symptoms and Signs of Heat Rash Symptoms, Causes, Pictures, Remedies, and Treatment

Doctor's Notes on Heat Rash Symptoms, Causes, Pictures, Remedies, and Treatment

Heat rash is a rash that breaks out when a person is overheated in warm conditions. The cause of heat rash is blockage of the sweat glands within the skin, which means that sweat cannot get to the skin surface to evaporate. Inflammation results, and this leads to a characteristic skin rash.  Blockage of the sweat glands can occur from heavy or tight clothing, areas of skin that rubs against adjacent skin (such as armpits or groin), heavy creams or lotions, or adhesive bandages.

The typical symptoms of heat rash are a bumpy, red, itchy skin rash, as well as a burning sensation or prickly feelings. Areas of the body commonly exposed to the sun like the hands, face, and neck are common locations for heat rash. Associated symptoms can include bumps on the skin that look like tiny blisters.

Medical Author:
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.