Abstract: An intestinal probe comprises a bladder and an axially expandable bellows connected with the bladder and being designed such that it changes its dimensions reversibly in its axial direction dependent on the pressure in its interior. A tube is provided with a lumen for the supply and removal of inflation medium to the bladder and bellows, the bladder and bellows being interconnected through a throttling valve. The throttling valve ensures that the inflation of the bladder is delayed relative to the axial expansion of the bellows and that the deflation of the bladder is delayed relative to an axial contraction of the bellows so that the intestinal probe, by using one lumen only for inflation medium, can be advanced stepwise through a gastrointestinal canal.