Prickly heat in adults is caused by the blockage of small sweat ducts, which is easy to appear when the body is hot, humid and airless. The scientific name of prickly heat is prickly heat rash, which is caused by hot and humid environment, small evaporation of sweat, and accumulation of sweat under the skin, which makes the skin swollen and presses the sweat ducts, leading to the blockage of sweat ducts. Prickly heat is common in the summer, and it occurs in infants and young children and people who are bedridden for long periods of time. Adults are more prone to prickly heat if they wear airtight clothes, wear bandages or medical tapes for a long time, or live in the basement. Adults with prickly heat should leave hot and humid environments and apply glycerite lotion or boric acid lotion as prescribed by the doctor. When the weather is hot, it is important to open windows and take baths regularly. Bedridden patients should turn over and scrub frequently to keep their bodies dry and clean.