The present disclosure relates to a method for operating a pharmacy order-picking device. The present method reduces the susceptibility of the pharmacy order-picking device to disruption. To detect a positioning deviation of the control appliance in the horizontal direction, at least one desired value of at least one reference position is made available, the control appliance is brought to a position corresponding to the desired value in the horizontal direction and, when a signal characteristic of a reference position is detected, an actual value of this reference position is determined. A desired value is compared with a corresponding actual value, or two actual values are compared with each other, and a deviation is determined. If a deviation is determined that exceeds a limit value, a signal pointing to the need for a correction is output. Depending on the deviation, automatic correction of the position deviation can be performed.