A high pressure delivery device for deliveringa medicament includes a first chamber for storing asupply of the medicament and a second chamber in fluidcommunication with the first chamber. A fluid connectionpath is in fluid communication with the second chamberfor administering the medicament. A valving system is influid communication with the first chamber, the secondchamber and the fluid connection path. The valving systemallows a dose of the medicament to be injected fromthe first chamber into the second chamber while substantiallypreventing backflow of the dose into the first chamberand substantially preventing leakage through the fluidconnection path. The valving system also allows the dosein the second chamber to be administered through the fluidconnection path while substantially preventing the dosefrom flowing back into the first chamber.
