Abstract: An injectable or implantable medical device having orifice(s) on the surface that release an active agent with zero-order release kinetics is described herein. The device is a hollow matrix of any size or shape, which can be made from both metal and non-metal surfaces. The device comprises of a reservoir capable of releasing at least one therapeutic, diagnostic, or prophylactic agent via the orifices to the desired anatomical site. The developed device, due to its composite structure, has the ability to combine several release mechanisms, leading to zero-order release kinetics for most of the time. The composition provides zero-order kinetics, in part, because the diffusion rate of the drug from the device is slow which enables sink conditions. Hence, no back transfer or build up of drug occurs at anytime. Polymers are not required for controlled release.