A drug delivery device includes a cartridge (211) for storing a medicament and a needle (203) communicating with the cartridge (211) for injecting a medicament dose. A rack (241) is movably disposed in the cartridge (211) and is engageable with a stopper (213) for expelling the medicament dose from the cartridge (211). A lever assembly (231) has a lever arm (233) connected to a lever gear (230). The lever gear (232) is engaged with the rack (241) such that rotation of the lever arm (233) rotates the lever gear (232) during injection of the medicament dose, thereby moving the rack (241) and stopper (213) through the cartridge (211) to deliver the medicament dose.