An endoscopy capsule (6) contains on one side of its housing (10), a sensor (12) for detecting a metabolic product of a bacterium located in or on the wall of a hollow organ (2) of the human or animal gastrointestinal tract, particularly in the stomach wall. The specific weight of the endoscopy capsule (6) is greater than the specific weight of a liquid (4) located in the hollow organ (2) and the mass centre of gravity (14) of the endoscopy capsule (6) is spaced apart from the volume centre of gravity (16) of the displaced liquid (4), wherein mass centre of gravity (14) and volume centre of gravity (16) define a straight connecting line (18) on which the sensor (10) is arranged on that side of the housing (10) adjacent to the mass centre of gravity (14). This ensures that the endoscopy capsule (6) is always in contact with the wall of the hollow organ (2) via the housing side on which the sensor (10) is arranged.
