Autoinjector having a pre-filled syringe, a piston rod (1005), an injection spring (1008), a movable element (1004； 1006), an acoustic and/or tactile indicating device (1500) having a key (1121), said key having a shaft part (1120), which extends inside the piston rod (1005), and a head part (1122), said movable element having at least one deformable tab (1510； 1520), said piston rod (1005) exerting traction on said head part (1122) via said shaft part (1121) of said key (1120) at the end of injection, thereby permitting a radial deformation of said at least one deformable tab and an axial movement of said movable element under the effect of said injection spring (1008), said movement generating an acoustic and/or tactile indication for the user.
