A Review of Patent Literature for Iontophoretic Delivery and Devices

Skin forms a protective barrier to the entry of foreign molecules, especially water soluble compounds. Iontophoresis, one of the promising approaches to deliver water soluble drugs through the skin, has already been approved by FDA to deliver lidocaine and fentanyl. Iontophoresis involves application of current (< 0.5 mA/cm(2)) to push charged molecules into, or across the body tissue and offers programmable delivery. This technique encompasses various fields such as developing a device, sophistication of the device, electrode design, electronics and formulation. In addition, combination strategies with other enhancement techniques, is also gaining importance. The focus of this review is on the latest developments in the field of iontophoresis including trends in device development, electrode design, formulation and therapeutic applications as described in the patent literature.