An iontophoresis device activated in use, which is capable of supplying a dissolution liquid in an amount that depends on the amount of a drug when it is used, is provided.This iontophoresis device activated in use comprises: an absorber 11 formed of a material containing a dry drug 10 and capable of absorbing a liquid a wall material 13 disposed around the absorber 11, having an adhesive layer 12 on the undersurface thereof a support 15 disposed on the absorber 11 and the wall material 13, having an opening 14 in the central portion thereof an electrode 25 disposed on the undersurface of the support 15 a diaphragm 20 disposed on the support 15 and a dissolution liquid reservoir 18 disposed on the diaphragm 20, retaining a dissolution liquid for dissolving the drug between the diaphragm 20 and itself, and having a protruding portion 17 for destroying the diaphragm 20 by pressing force. The protruding portion 17 has a linear apical portion, for example, and it is disposed so that it is allowed to come into contact with or is close to the diaphragm 20. A liner 19 is removably attached on the undersurface of both the absorber 11 and the adhesive layer 12.
