Subjects will participate in 4 study day visits that will be scheduled about 1- week apart. During the first study visit, the investigators will compare sweat collected following pharmacological stimulation of sweating (using the drug pilocarpine) to sweat collected following physiological stimulation of sweating (using a stationary bicycle). During the second study visit, the investigators will collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) and also the upper surface of the thigh (near the knee). During the third study visit, the investigators will collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of both forearms (near the wrist). During the fourth study visit, the investigators will collect a sweat sample following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) and a blood sample (about one teaspoon) from the other arm. After blood and sweat collection, participants will consume 400 mg (two tablets) of ibuprofen. The investigators will then collect blood and sweat from 30 minutes, 2 hours and 4 hours after participants consume the ibuprofen.