An iontophoresis patch which outputs an electric current from an energizing device to an external conductor comprises: a donor portion that has a first contact member a reference portion that has a second contact member and is located on the external conductor away from the donor portion and an electrode body that has a first electrode and a second electrode and that extends across the donor portion and the reference portion. The electrode body has a single-sided wiring structure in which the first electrode and the second electrode are formed by a conductive ink being printed on one side of a film, the printing pattern of the first electrode has a gap area in which the conductive ink is not printed, and the film and the first contact member are transparent.
