Prickly heat often appears in hot, humid weather, when sweat becomes trapped beneath the skin. It can cause small rashes, burning, irritation, redness, and itching, especially on the neck, chest, back, or in skin folds. Sweating a lot, wearing tight clothes, and staying in the heat too long can make it worse and make your skin more sensitive. Calamine lotion is often used to help soothe the skin and ease irritation and itching over time. Taking cool baths, wearing loose cotton clothes, keeping the air flowing, and avoiding too much sweating can help the rash heal faster. Try not to use heavy, oily creams or wear tight synthetic clothes, as these can block sweat glands and make irritation worse. Staying out of direct heat and changing out of sweaty clothes quickly can also help you feel better while you recover. Usually, the rash gets better slowly with cooling care and by protecting your skin. Consult a doctor if the rash becomes painful, develops pus, spreads quickly, or comes with fever, severe burning, or swelling, since this could mean an infection or another skin problem.