An implantable pump and methods for detecting leaks in an implantable pump are provided. In one embodiment, the implantable drug pump includes a housing having at least one inlet port and an outlet port formed therein. The outlet port is adapted to communicate with a catheter for delivering fluid to a patient's body, and the inlet port(s) are effective to deliver fluid into the housing. The housing further includes at least one reservoir disposed therein and effective to contain a fluid. In use, the pump preferably includes a fluid having one or more drugs disposed in at least one of the reservoirs, and a radiopaque fluid disposed in one of the reservoirs. A user programmable control mechanism is coupled to the drug pump and is effective to selectively control movement of the valves between the open and closed positions.