Described are methods and devices (100) for measuring a sweat property of skin (12) in response to at least one test material or component (172, 174, 176, 178). Embodiments of the device include a plurality of different sweat stimulation sites. The Sweat stimulation sites may include one or more sweat stimulant reservoirs (142, 144, 146, 148) configured to deliver a sweat stimulant to the surface of the skin (12). Embodiments may also include at least one electrode (150, 152, 154, 156, 158) for measuring a sweat property or to iontophoretically deliver the sweat stimulant from the reservoir (142, 144, 146, 148). In embodiments, the sweat stimulant is selected from acetylcholine, carbachol, methacholine, bethanechol, muscarine, pilocarpine, oxotremorine, and combinations thereof.