1. A diabetes management system, comprising: (a) a blood glucose meter measuring blood glucose level data; and (b) a portable microprocessor-based unit in communication with the blood glucose meter such as to be capable of accessing said blood glucose level data; (c) wherein input data corresponding to said blood glucose level data is used in a program of instructions running on the portable microprocessor-based unit; and (d) wherein said program of instructions includes instructions to send a signal to inject insulin based upon said blood glucose level data.