A syringe for dispensing anesthetic from a cartridge having an interior wall defining a hollow interior sized and shaped for receiving a dose of anesthetic, and a piston. The syringe includes a tubular plunger slidably received in the hollow interior of the tubular cartridge. The plunger has a hollow interior extending between a distal end shaped for engaging the piston and an open proximal end. The syringe includes a plunger rod slidably received in the hollow interior of the tubular plunger. The rod has a sharp distal end adapted to penetrate the piston, a proximal end, and a length extending between the distal end and the proximal end sized so a delivery portion of the rod extends through the piston into the cartridge when the rod is driven through the piston. The delivery portion includes a recess for receiving a buffering agent to reduce acidity of the dose of anesthetic.