The present invention relates to a dialysis machine, a method for operating a dialysis machine and a device for using a dialysis machine, wherein parameters for the dialysis treatment are entered, wherein, on the basis of a prescribed model including at least the previously entered parameters for at least one concentration of a dissolved substance, the profile of the change in concentration to be expected as a result of the dialysis treatment and/or the end value to be expected of the concentration of this substance in the vascular circulation of the patient is calculated and evaluated, and at least one signal and/or an indication is output by output means indirectly and/or directly in dependence on the evaluation of the profile of the change in concentration to be expected as a result of the dialysis treatment and the end value to be expected of the concentration of the substance and/or the dialysis treatment or the machine settings for the dialysis treatment is/are indirectly and/or directly influenced.
