Abstract: A device for delivering a liquid, semiliquid or solid beneficial agent into the mouth of a human or animal is disclosed. The device has a size and shape adapting it to be comfortably retained in the mouth for extended periods of time. The device may be formulated in one of two forms: 1) one form comprises a wall surrounding a hollow compartment holding the beneficial agent. A passageway in the wall connects the agent with the exterior of the device. The wall is impermeable and, with the exception of the passageway, fluids may not enter into the hollow compartment, or escape from the hollow compartment into the mouth. The size and configuration of the passageway determines the rate at which the agent is released into the mouth.