A dose setting mechanism for an injection device for injecting a dose of medication from a reservoir which comprises a housing with a distal end and the housing having a longitudinal axis and whereby the reservoir is located at the distal end of the housing. Furthermore the dose setting mechanism has afirst part which is rotated during the setting of a dose, a second part which does not rotate during the setting of a dose and a third part which is rotated by the first part during dose setting with a given transmission ration. The second part comprises a stop member which prevents further rotation of the third part when the third part has been rotated over a specific angle, thereby preventing the setting of a dose which exceeds a predetermined amount of medication from the reservoir. The dose setting mechanism is characterized by that the third part is axially shifted back and forth by the first part during dose setting between a proximal and a distal position and whereby during each axial shift the third part is rotated over a discrete angular step.
