An injection device provides a casing which accommodates or forms a reservoir for a liquid drug； a plunger rod which can move relative to the casing in an axially forward direction to deliver the drug； a dosing means which can move in the forward direction relative to the casing to prime the reservoir and which can rotate relative to the casing for selecting a dose to be injected, wherein rotation of the dosing means relative to the casing is prevented until a priming operation for priming the reservoir is completed； d) wherein the dosing means comprises a dosing control means which is configured to enable rotation of the dosing means at the end of the priming stroke for selecting the dose and to prevent a rotation of the dosing means back into the position which the dosing means had at the end of the priming stroke relative to the casing.
