An infusion system for use with a total parenteral nutrition source of TPN solution and an insulin source of insulin solution to provide concurrent TPN/insulin infusion, the infusion system comprising: a fluid administration set having a primary line in fluid communication with the TPN source, a secondary line in fluid communication with the insulin source, and a common outlet line connected to and in operative fluid communication with the primary line and the secondary line; a positive displacement pump operable to removably receive the fluid administration set, the pump having a drive mechanism being operable on the fluid administration set to concurrently move the TPN solution through the primary line to the outlet line in response to a TPN solution flow rate signal and the insulin solution through the secondary line to the outlet line in response to an insulin solution flow rate signal; a flow controller operable to provide the TPN solution flow rate signal and the insulin solution flow rate signal to the drive mechanism of the pump, wherein the flow controller is further operable to vary the TPN solution flow rate signal and the insulin solution flow rate signal to vary a ratio of TPN solution to insulin solution provided to the common outlet, wherein the flow controller is further operable to ramp the TPN solution flow rate signal from a value corresponding to a TPN dose rate of zero to a value corresponding to a continuous phase TPN dose rate over a user selectable duration in a TPN ramp phase; and a glucose sensor operable to be connected to the patient to monitor glucose level and to provide a glucose signal to the flow controller, wherein the flow controller is further operable to vary the insulin solution flow rate signal from a first insulin solution flow rate signal to a second insulin solution flow rate signal in response to the glucose signal. a fluid administration set having a primary line in fluid communication with the TPN source, a secondary line in fluid communication with the insulin source, and a common outlet line connected to and in operative fluid communication with the primary line and the secondary line; a positive displacement pump operable to removably receive the fluid administration set, the pump having a drive mechanism being operable on the fluid administration set to concurrently move the TPN solution through the primary line to the outlet line in response to a TPN solution flow rate signal and the insulin solution through the secondary line to the outlet line in response to an insulin solution flow rate signal; a flow controller operable to provide the TPN solution flow rate signal and the insulin solution flow rate signal to the drive mechanism of the pump, wherein the flow controller is further operable to vary the TPN solution flow rate signal and the insulin solution flow rate signal to vary a ratio of TPN solution to insulin solution provided to the common outlet, wherein the flow controller is further operable to ramp the TPN solution flow rate signal from a value corresponding to a TPN dose rate of zero to a value corresponding to a continuous phase TPN dose rate over a user selectable duration in a TPN ramp phase; and a glucose sensor operable to be connected to the patient to monitor glucose level and to provide a glucose signal to the flow controller, wherein the flow controller is further operable to vary the insulin solution flow rate signal from a first insulin solution flow rate signal to a second insulin solution flow rate signal in response to the glucose signal.