A medication delivery device (1) is provided which is switchable between an operational state and a resetting state and which comprises a housing (13) having a proximal end (8) and a distal end (7), a piston rod (12) being moveable in a distal direction with respect to the housing (13) for medication delivery, a conversion element (38) adapted to at least partially convert a rotational movement of the piston rod (12) into an axial movement of the piston rod (12), coupling means (39) prevented from rotational movement with respect to the housing (13) and adapted to engage with the conversion element (38) in the operational state, a drive assembly (3) comprising at least two drive assembly members and adapted for moving the piston rod (12) in the distal direction, and a resilient member (31) adapted to provide a force on the drive assembly (3) for engagement of the drive assembly members. In the operational state of the device (1) the coupling means (39) is engaged with the conversion element (38), the conversion element (38) thereby being prevented from rotation with respect to the housing (13). In the resetting state of the device (1) the coupling means (39) is disengaged from the conversion element (38) under force of the resilient member (31), the conversion element (38) thereby being allowed to rotate with respect to the housing (13) and thereby allowing a resetting of the device (1).
