An implantable drug-delivery device comprises a drug reservoir (108), a needle entry port (116) and a throat (128) for receiving a refill needle (120) therethrough. The device also comprises a vestibule (132) into which the throat opens that is wider (w2) than the throat (128). The vestibule has a stop (152) on a wall (148) opposite the throat for halting progress of a needle into the vestibule through the throat, and is in fluid communication with the dry reservoir.