Abstract: A device (1) fills a flexible pouch (100) with medicinal fluids. The pouch is mounted with its distal end (113) upward and attached to a filling infuser (110) which is supported in a supporting bore (121). A neck end of the supply container (200) which carries a resilient cap (202) is inserted into the bore such that the filling infuser pierces the cap. A flexible bladder (31) or a squeeze bulb (33) is connected with an air inlet (116) of the filling infuser to inject pressurized air into the supply container and accelerate the transfer of medicinal liquids from the supply container to the flexible pouch.