US Patent 9572773 Layered drug delivery device

The layered drug delivery devices of the present invention have an outer side and an inner side. The device includes, in order from the outer side to the inner side, a first layer and a second layer. The first layer wherein the first layer is water insoluble, water swellable, and water permeable. The second layer includes a therapeutic amount of a water soluble drug and a water soluble mucoadhesive film. The second layer is disposed such that water passing through said first layer solubilizes the drug. The said solubilized drug then can permeate through a mucosal membrane when the inner side is in contact with the mucosal membrane. The drug delivery device is in sheet form.