The invention concerns a method of filling a container (1) with a liquid drug from a drug reservoir (2) comprising the steps: a) connecting the container (1) and the drug reservoir (2) with a cannula (3) so that they communicate with each other b) reducing the inside volume of the container (1), thereby displacing a gaseous medium from the container (1) into the drug reservoir (2) c) increasing the inside volume of the container (1), thereby displacing liquid drug from the drug reservoir (2) into the container (1) and d) disconnecting the filled container (1) and the liquid drug reservoir (2). The steps b) and c) are successively performed more than once before step d) is performed, thereby stepwise increasing the amount of liquid drug contained inside the container (1). By means of the method according to the invention it becomes possible to significantly reduce the risk of a formation of foam and air bubbles within the liquid drug that is filled into the container.
