Systems, methods and/or devices for treating diabetes mellitus by alleviating glucotoxicity and restoring pancreatic beta-cell function, comprising at least a first memory for storing data inputs corresponding at least to one or more components in a patient's present insulin dosage regimen, and data inputs corresponding at least to the patient's blood-glucose-level measurements determined at a plurality of times, and a processor operatively connected to the at least first memory. The processor is programmed at least to determine from the data inputs corresponding to the patient's blood-glucose-level measurements determined at a plurality of times whether and by how much to vary at least one of the components of the patient's present insulin dosage regimen. Also disclosed are systems, methods, and/or devices for alleviating glucotoxicity and restoring pancreatic beta-cell function, comprising establishing the patient's current glycemic state relative to a desired glycemic range and determining from at least one of a plurality of the data corresponding to the patient's blood glucose-level measurements whether and by how much to adjust at least one of the components in the patient's present insulin dosage regimen.