A disposable injector with a housing (10) in which at least one mechanical spring energy accumulator (50), at least one cylinder-piston unit (100), at least one piston-actuating ram and at least one release unit are arranged. The housing has at least one draw hook (21) which has at least one supporting surface in the region of its free end. The piston-actuating ram bears against the supporting surface. The blocking position of the draw hook is ensured by a release element positioned in a blocking position. The release (82) has a release position which brings about an inevitable lateral retraction of the draw hook&mdash；with the piston-actuating ram being released.
