Heat rash is a skin condition in which blocked sweat glands cause tiny red bumps to appear on the skin, according to the American Academy of Pediatrics. Babies and children are more prone to developing heat rash than adults.
Hot and humid weather encourages the development of heat rashes, according to the American Academy of Pediatrics. This skin condition tends to appear in areas where skin rubs against skin, such as in the folds of the neck, around the diaper area, and on the arms, legs, and upper chest.
Excessive sweating and being overdressed for the weather can increase a person's risk of developing a heat rash, according to FamilyDoctor.org. Cotton clothing wicks away moisture and helps prevent heat rash, while baby powders and ointments can block sweat pores and make the condition worse. Air conditioners and fans keep the skin cool, which helps prevent and treat heat rash.
Cool compresses provide immediate relief for skin affected by heat rash, according to FamilyDoctor.org. Wearing loose clothing that does not rub against the affected area and keeping the skin cool and dry promote healing.
Most instances of heat rash naturally go away in a few days, according to FamilyDoctor.org. Severe itching, swelling or oozing signal a more serious problem and should be reported to a doctor.