The invention concerns a method for removing gas and/or gas bubbles (6) from a liquid medicament (5) stored in a reservoir (1) for an infusion pump device. The reservoir (1) comprises a displacing member (15, 13) which is at least partly displaceable relative to the reservoir (1) thereby enabling receiving mechanical oscillations in order to generate mechanical waves in the liquid medicament (5). The method comprises: providing the reservoir (1) and transmitting a mechanical oscillation (70) to the displacing member (15, 13) of the reservoir (1) thereby generating a mechanical wave (7) in the liquid medicament (5) for removing gas and/or gas bubbles (6) from the liquid medicament (5).
