Your skin feels so hot and prickly, you're considering actually crawling out of it.
The key is to chill out, literally. Take a cold shower, change into loose-fitting clothes, and avoid thick, heavy moisturizers, which can exacerbate a heat rash. Speed your skin's natural recovery process by dabbing the affected area with calamine lotion—"the combination of zinc and ferric oxide helps keep it cool," says Brandt. One thing to skip? Makeup. It can prolong the rash by blocking sweat ducts. The good news: You won't have to stay in hiding for long. "Cool down, and the rash should clear up within a day or two," says Brandt.