An apparatus and system diabetes management. The apparatus comprises a body which houses: (i) 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 the patient's blood-glucose-level measurements determined at a plurality of times; (ii) a processor operatively connected to the at least first memory, the processor 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 one or more components of the patient's present insulin dosage regimen; (iii) a display screen operatively connected to the processor; (iv) a quantity of insulin; (v) a needle communicating with the quantity of insulin for delivering insulin to the patient; (vi) means for effecting delivery of a portion of the quantity of insulin to the patient via the needle; and (vii) metering means for controlling the portion of the quantity of insulin delivered to the patient via the needle.