For controlling the movement of the push device of a pump of the syringe driver-type, the pump comprising a casing (100), a syringe cradle (200) for a syringe (400), a push device (300) mobile relative to the casing (100) and capable of being driven in rotation parallel to the longitudinal axis of the syringe by driving means, clutch means (310, 350, 351) for engaging or disengaging the push device on the driving means, the push device is disengaged from the driving means, in order to move it manually, and the presence or absence of a contact between the push device and the syringe head is determined. If the push device is not in contact with the syringe head, it is advanced manually. Blocking of the advance movement of the push device is triggered only if, at the beginning, the push device was not in contact with the syringe head.