Systems and methods for administering drugs to a patient, including a syringe system. The syringe system includes a plastic needle coupled to an end of a syringe barrel, the needle including a proximal taper and a distal taper. A cannula assembly is removably coupled to the plastic needle, the cannula including mating surfaces for the proximal and distal tapers of the plastic needle. The syringe system can also include a cannula cover with a first and second end with different sizes to respectively attach to the cannula assembly and the barrel when the cannula assembly is removed. The cannula may have a distal tip cut at an angle to ensure maximum removal of drug from a given vial.
