A cartridge (100) for containing and dispensing a medicament, the cartridge (100) including a cartridge body (104) having an interior cavity (108) therein, a stopper (112) movably disposed within the interior cavity (108), and a septum (116, 148) disposed at an opposite end of the interior cavity (108) from the stopper (112), for containing the medicament within the interior cavity (108). The cartridge (100) also includes a connection thread (120) integrally formed as a unitary construction of the cartridge body (104), the thread (120) being disposed at a first end of the cartridge body (104) for connecting a pen needle directly to the cartridge body (104) to pierce the septum (116, 148) and provide communication between the medicament and a patient end of the pen needle. The cartridge (100) additionally includes a connector (128) for directly connecting the cartridge body (104) to a dosing mechanism for moving the stopper (112) toward the septum (116, 148) to dispense the medicament.