The invention refers to an auto-
injector for administering a medicament (M), comprising of a
chassis, a
syringe with a hollow needle and a stopper; a drive spring capable of, upon activation: advancing the needle (3), injecting the medicament (M), and retracting the
syringe with the needle after delivering the medicament (M); and; activating means arranged to lock and release the drive spring, wherein the drive spring is a compression spring arranged to be grounded at a distal end in the
chassis for advancing the needle and for injecting the
dose of medicament (M) via a
plunger and wherein the drive spring is arranged to have its ground in the
chassis switched to its proximal end for retracting the
syringe. A
refraction sleeve is axially movable arranged around the syringe, wherein the retraction sleeve is fixable in a maximum proximal position for providing ground at the distal end of the drive spring, wherein the retraction sleeve is arranged to take the syringe with it when released and translated in distal direction (D), wherein the compression spring is wrapped over the retraction sleeve with its distal end bearing against a thrust face on the retraction sleeve and with its proximal end bearing against a thrust collar arranged to be coupled to the
plunger for joint axial translation for advancing the needle and for injecting the
dose of medicament (M) and to decouple from the
plunger for retraction.