A MEDICAL INJECTION DEVICE WITH A CLEANING CHAMBER

The invention relates to an injection device for injecting a liquid drug. The injection device comprises a housing assembly (10, 20;110, 120) supporting a non-removable cartridge (5;105) having an interior chamber containing the liquid drug to be injected and a reusable needle cannula (30;130) connected to the cartridge. A needle shield assembly (40, 40A, 40B, 60;140, 140A, 140B) provided with a cleaning chamber (51;151) containing a volume of a cleaning agent for cleaning at least the distal tip (33;133) of the needle cannula (30; 130) between subsequent injections is further provided. The needle shield assembly (40, 40A, 40B, 60;140, 140A, 140B) is axially movable in a proximal direction in relation to the housing assembly (10, 20;110, 120) from a first position to a second position upon rotation of at least a part of the needle shield assembly (40, 40A, 40B, 60;140, 140A, 140B), wherein the first position is a position in which the distal tip (33;133) of the needle cannula (30;130) is located inside the cleaning chamber (51;151) thereby cleansing the distal tip (33;133) of the needle cannula (30;130), and the second position is a position in which the distal tip (33;133) of the needle cannula (30;130) is located outside and distal to the cleaning chamber (51;151) for equalizing the pressure in the cartridge.