A medical device that delivers therapeutic agent to the tissue within the bodily passageway while simultaneously permitting flow of bodily fluids past the location of treatment. The medical device includes an inflatable balloon and optionally one or more balloon wall openings that are configured to allow fluid in the interior of the inflatable balloon to flow through the inflatable balloon when the inflatable balloon is pressurized by the fluid in the interior of the inflatable balloon. During the inflation of the inflatable balloon at the treatment site, the flow of blood through the blood vessel is maintained across the treatment site by use of one or more bypass passageways in the medical device.
