Try them when: You want an alternative to pills.
How they work: When applied to the skin, these creams cause nerve endings to feel either heat or cold, which dulls pain. Ingredients to look for: cooling menthol; salicylate, the compound in aspirin; or capsaicin, a heat-stimulating substance found in hot peppers (try Capzasin HP, $14 at drugstores).
Good to know: Some creams can irritate the skin or cause redness, says Katz. Wash your hands after applying, and—common sense—don’t get them in your eyes.