A disposable injector comprising a housing, a spring-loaded piston-actuating plunger arranged in the housing and able to be released by a trigger unit. A cylinder-piston unit comprising a cylinder and a piston that is positioned at a distance from the piston-actuating plunger. A closed layer made on an elastically-deformable material surrounds the piston-actuating plunger in at least some sections and projects beyond same in the trigger direction, resulting in a disposable injector that will not alarm a patient during use thereof.
