Abstract: An applicator (26) for a releasable coupling of a transpyloric and, if applicable, transduodenal bypass device (1) comprising a tubular, preferably radially collapsible and self-erecting transpyloric conducting element (4,7), which is or has to be placed in a patient in such a way that it penetrates the pylorus of the patient and is provided with a central conducting lumen comprising an upstream mouth to be placed antegrade of the pylorus and a downstream mouth to be placed retrograde of the pylorus, for (i) accepting the chyme from the stomach, for (ii) bypass-type conducting of the chyme through the pylorus and, if applicable, through the duodenum or a part of the duodenum, and for (iii) releasing the chyme in or beyond the duodenum of the patient, to an endoscope or a catheter having an elongated shaft (28), on the external surface of which the bypass device (1) can be placed and/or plugged in order to insert the bypass device (1) under direct guidance of the endoscope or catheter from the outside of the p

Abstract: The invention relates to a transpyloric device for accepting chyme from the stomach and conducting said chyme on in a bypass-like manner through a patient's duodenum; said device is held in place by balloon segments which sit on a preferably radially collapsible and self-erecting transpyloric conducting element; the filling level of the balloon segments, and thus the axial sealing force acting primarily on the shoulder surfaces of the pylorus or the surrounding area thereof, can be adjusted by the user, and the force applied to the stomach and duodenum structures adjoining the pylorus is reduced to a level that is permanently bearable for the organs even when the filling pressure of the segments rolling against each other is elevated. The invention also relates to an applicator for putting a bypass device of said type in place in the region of the transition from the stomach to the duodenum.