CONTROLLED RELEASE DEVICE

摘要

A controlled release device is provided herein. The device includes (i) a hydrogel, and incorporated therewith (ii), an active substance. At least part of at least one surface of the device comprises (iii) a layer which is impermeable to aqueous media. Such device is an improved so-called "zero order" release device in which the release is sustained over a prolonged period of time.