Dispositivo de inyección médico

The invention relates to a prefilled injection pen for apportioning multiple set doses of a liquid drug. The injection pen comprises a housing structure with a distal part supporting a needle cannula and which distal part is covered by a protective cap between subsequent injections. Further, an axially movable shield for covering the distal tip of the needle cannula between injections is provided. This axially movable shield is rotatable relatively to the housing structure between a first locked position and a second unlocked positon. In the first position, the axially movable shield is prevented from moving proximally and in the second position the axially movable shield is allowed to move proximally. The removable protective cap is rotatably coupled to the housing structure and further comprises means for engaging the axially movable shield.