A method is provided for extracting liquid from a liquid dispenser The dispenser includes a liquid container and, connected to the container, a liquid dispensing device is able to take up liquid from the container and convey it along a path as far as at least one liquid outlet so as to dispense this liquid to the outside. The method includes a step of injecting a volume of extraction gas under pressure into the container so as to apply pressure to the liquid of the container in order to cause it to flow along at least part of the device and allow a predetermined quantity of liquid to be extracted from the dispenser.