The invention refers to a handheld injection device comprising a housing (10), a rotatable dose setting member (80, 60), a power reservoir (90) coupled to the dose setting member wherein energy is stored in the power reservoir during rotation of the dose setting member, a release member (70) for receiving a force from a user, and a rotatably arranged drive member (40) engaging with a drive track (32) of a piston rod (30). The device further comprises a release clutch (100 230) rotationally constrained to the housing and releasably engaging the drive member, wherein the release clutch is positionable in a first axial position when the release member is in a dose setting position and in a second axial position when the release member is in a dose injection position. The axial position of the drive member within the housing remains constant when the release member is in its dose setting position and in its dose injection position.
