Iontophoresis patch

An iontophoresis patch having a first contact member and a second contact member for outputting an electric current from an energizing unit to an external conductor upon being placed in contact with the external conductor, comprising:

• a donor portion having the first contact member, the first contact member containing a drug to permeate into the external conductor;
• a reference portion having the second contact member and which is placed on the external conductor away from the donor portion;
• an electrode body having a flexible base, and a first electrode and a second electrode which are disposed on the base, for supplying electric currents from the energizing unit respectively to the first contact member and the second contact member, the electrode body being disposed over the donor portion and the reference portion;
• a pair of connection terminals through which the energizing unit is disposed on the iontophoresis patch and which are electrically connected to the first electrode and the second electrode, wherein the pair of connection terminals are disposed on only the reference portion;
• wherein the electrode body has a one-sided interconnect structure in the donor portion wherein the first electrode is disposed on a surface of the base that faces the external conductor;
• and
• the electrode body has a double-sided interconnect structure in the reference portion wherein after the second electrode and a first contact terminal line and a second contact terminal line for interconnecting the pair of connection terminals and the first electrode and the second electrode are formed on the same surface of the base as the surface on which the first electrode is disposed, a portion of the base on which the first contact terminal line and the second contact terminal line are formed is folded back on itself into a two-layer structure, so that the second electrode is disposed on a surface of the reference portion that faces the external conductor, and terminal bases connected to the first contact terminal line and the second contact terminal line and also connected to the pair of connection terminals are disposed on a surface of the reference portion that is opposite to the surface thereof facing the external conductor.