Implantable medical devices (IMDs) detect and deliver therapy through a lead. Typically, a stimulation electrode at the distal end of a lead is positioned near or in tissue so that electrical stimuli may be delivered. To reduce or prevent inflammation of the tissue in response to the stimulation electrode, the distal end of the lead includes a monolithic controlled release device that releases an anti-inflammatory agent such as a steroid. It is desirable to develop devices that are able to chronically release anti-inflammatory agents in the vicinity of a stimulation electrode.