The invention relates to a disposable injector with acylinder/piston unit that can be filled at least temporarily withactive substance, with a housing in which a pretensioned andreleasable mechanical spring energy reservoir is arranged, andwith at least one piston-actuating ram positioned between thespring energy reservoir and a piston of the cylinder/piston unit.The piston-actuating ram has two guide arms or draw hooks thatengage around the housing in some areas. In addition, the piston-actuating arm is separable from the housing by means of therelaxing spring energy reservoir.With the present invention, a disposable injector is developedwhich, with a small overall size, comprises only a small numberof components and, while being easy to handle, ensures safestorage and operation.
