An automaton (10a-10b) for packaging prescriptions for a set of patients (Des), by means of a database comprising a prescribed quantity (Qua) of a drug associated with each patient (Des), said automaton (10a-10b) comprising: - cups intended to be dispensed to the various patients (Des) with the prescribed quantity (Qua) of drug; - a conveyor (16a-16b) for moving the cups and having through openings for receiving the cups in order to move them to a filling station, including: ▪ at least one reservoir (R1-R4) of drug; ▪ a filling head (15a-15b) for dispensing the drug; ▪ a pump (14a-14b) connected between the reservoir (R1-R4) and the filling head (15a-15b); and ▪ a motor operating the pump so as to dispense the drug contained in the reservoir (R1-R4) at the filling head (15a-15b); and - a monitoring member, connected to the database, configured to control the pump (14a-14b) so as to dispense the prescribed amount (Qua); characterized in that said filling station also comprises: - a compensating electromagnetic force balance comprising a plate, and an actuator for moving said balance configured to move said balance between two positions: ▪ a filling position in which the plate lifts a cup toward said dispensing head (15a-15b) so that the lifted cup is no longer supported by the conveyor (16a-16b) and so that the balance can measure the change in weight (Mes) of the lifted cup during filling thereof; and ▪ a conveying position in which said plate is not in contact with a cup so that the conveyor (16a-16b) can move the cups; - said monitoring member being configured to control the motor according to the measured weight (Mes) by said compensating electromagnetic force balance until the measured weight (Mes) corresponds to the prescribed quantity (Qua). - cups intended to be dispensed to the various patients (Des) with the prescribed quantity (Qua) of drug; - a conveyor (16a-16b) for moving the cups and having through openings for receiving the cups in order to move them to a filling station, including: ▪ at least one reservoir (R1-R4) of drug; ▪ a filling head (15a-15b) for dispensing the drug; ▪ a pump (14a-14b) connected between the reservoir (R1-R4) and the filling head (15a-15b); and ▪ a motor operating the pump so as to dispense the drug contained in the reservoir (R1-R4) at the filling head (15a-15b); and ▪ at least one reservoir (R1-R4) of drug; ▪ a filling head (15a-15b) for dispensing the drug; ▪ a pump (14a-14b) connected between the reservoir (R1-R4) and the filling head (15a-15b); and ▪ a motor operating the pump so as to dispense the drug contained in the reservoir (R1-R4) at the filling head (15a-15b); and - a monitoring member, connected to the database, configured to control the pump (14a-14b) so as to dispense the prescribed amount (Qua); characterized in that said filling station also comprises: - a compensating electromagnetic force balance comprising a plate, and an actuator for moving said balance configured to move said balance between two positions: ▪ a filling position in which the plate lifts a cup toward said dispensing head (15a-15b) so that the lifted cup is no longer supported by the conveyor (16a-16b) and so that the balance can measure the change in weight (Mes) of the lifted cup during filling thereof; and ▪ a conveying position in which said plate is not in contact with a cup so that the conveyor (16a-16b) can move the cups; - said monitoring member being configured to control the motor according to the measured weight (Mes) by said compensating electromagnetic force balance until the measured weight (Mes) corresponds to the prescribed quantity (Qua). - a compensating electromagnetic force balance comprising a plate, and an actuator for moving said balance configured to move said balance between two positions: ▪ a filling position in which the plate lifts a cup toward said dispensing head (15a-15b) so that the lifted cup is no longer supported by the conveyor (16a-16b) and so that the balance can measure the change in weight (Mes) of the lifted cup during filling thereof; and ▪ a conveying position in which said plate is not in contact with a cup so that the conveyor (16a-16b) can move the cups; ▪ a filling position in which the plate lifts a cup toward said dispensing head (15a-15b) so that the lifted cup is no longer supported by the conveyor (16a-16b) and so that the balance can measure the change in weight (Mes) of the lifted cup during filling thereof; and ▪ a conveying position in which said plate is not in contact with a cup so that the conveyor (16a-16b) can move the cups; - said monitoring member being configured to control the motor according to the measured weight (Mes) by said compensating electromagnetic force balance until the measured weight (Mes) corresponds to the prescribed quantity (Qua).