A multifunctional glucose monitoring system and method of measuring glucose level, determining insulin dosage, and indicating insulin dosage on a syringe is disclosed. The multifunctional glucose monitoring system includes standard functionality with respect to acquiring a blood glucose reading. However, in addition, the multifunctional glucose monitoring system includes a dosage algorithm for calculating an insulin dosage based on the blood glucose reading and any other useful parameters, and includes a built-in marking device for marking the calculated dosage level on the barrel of an insulin syringe that is installed in the body of the multifunctional glucose monitoring system. A method includes the steps of measuring the glucose level, determining an insulin dosage, and indicating the insulin dosage on a syringe.