A sensor ( e.g., an optical sensor) that may be implanted within a living animal ( e.g., a human) and may be used to measure an analyte ( e.g., glucose or oxygen) in a medium ( e.g., interstitial fluid, blood, or intraperitoneal fluid) within the animal. The sensor may include a sensor housing, an analyte indicator covering at least a portion of the sensor housing, and one or more therapeutic agents. The one or more therapeutic agents may be incorporated within the analyte indicator, a membrane covering at least a portion of the analyte indicator, and/or one or more drug eluting polymer matrices that cover at least a portion of the sensor housing and are applied to the sensor housing via dip coating or spray coating.