An autoinjector (100) for expelling a dose of a drug from a held cartridge (600) is described. A needle shield (350, 380) is axially movable relative to a base (200, 220) between an extended position and a collapsed position to operate a trigger lock (328, 388) configured for releasably maintaining a plunger (310, 400) in an initial axial position against the force of an actuator (330). One of the needle shield (350, 380) and the base (200, 220) defines one or more contact surfaces (382) each being resiliently slideable over a respective cooperating ramp surface (212) formed in the other of the needle shield (350, 380) and the base (200, 220) to provide a resistance to movement of the needle shield (350, 380) during needle shield displacement from the extended position towards the collapsed position. A high resistance to movement is obtained in a first stage of said needle shield displacement followed by a low resistance to movement in a second stage.
