abstract |
Subsaturated, rate controlled delivery devices (1) for delivering an agent (5). The initial equilibrated concentration of the agent in the agent reservoir (3) and the adhesive (5) is below saturation. The initial loading of the agent in reservoir (3) is sufficient to prevent the activity of the agent in the reservoir (3) from decreasing by more than about 75 % and preferably no more than about 25 % during the predetermined period of administration. The thicknesses of the adhesive (5), rate controlling membrane (4) and reservoir (3) layers are selected so that at least 50 % and, preferably at least 75 % of the initial equilibrated agent loading is in the reservoir layer (3). The devices (1) are usable to deliver agents which are liquid at body temperatures such as benzotropine, secoverine, nicotine, arecoline, polyethylene glycol monolaurate, glycerol monolaurate, glycerol monooleate and ethanol, for example. |