1. A system for optimizing a patient's basal insulin dosage regimen over time, comprising a patient unit and a display unit, the patient unit comprising: a blood glucose meter for determining a blood glucose value from a blood sample, first controller and memory apparatus adapted to: store data representing an initial basal insulin dosage regimen, the dosage regimen comprising a recommended amount of an insulin-containing drug to be taken at recommended intervals, determine from blood glucose values determined at a plurality of times whether and by how much to vary the patient's present recommended amount of the insulin-containing drug in order to maintain the patient's future blood glucose level measurements within a predefined range, and create a blood glucose value log representing blood glucose values as a function of time, and structure to transmit log data to the display unit, the display unit comprising: structure to receive log data from the drug delivery assembly, display apparatus, second controller and memory apparatus to: store the received log data, and control the display means to at the same time display the blood glucose value log data and a recommended amount log as a function of time.