A cylinder-piston unit of a needle-free injector, with at least one cylinder accommodating an injection solution, at least one piston, and an adhesive coating arranged in the area of the free end face of the cylinder. The cylinder has a bottom portion, on which a discharge tube is arranged. An adhesive disc, which is displaceable in the direction of the centre line of the cylinder-piston unit between an installation position and an application position, is arranged on the discharge tube and/or on the bottom portion. The adhesive disc has an adhesive coating on each of the two end faces. In the installation position, the discharge tube can be sealed off in the adhesive disc. In the application position, the front edge of the discharge nozzle lies in the plane of the front adhesive coating or protrudes beyond this plane by at least 0.5 mm. A needle-free cylinder-piston unit of an injector whose discharge system is suitable for safely penetrating the outer layers of skin, covered by the term &ldquodermis&rdquo, in order to convey the injection solution into or under the skin.
