Abstract: An ampoule is disclosed having a stopper slidably mounted therein adjacent the proximal end and a rubber diaphragm secured to the distal end. An aperture barrier is provided in the ampoule between the proximal and distal ends, and has an aperture sealed by a plug. Sterile acidified liquid local anaesthetic is contained in an proximal compartment defined in the ampoule by the barrier and the stopper. Sterile alkaline neutralizing reagent is contained in the distal compartment defined in the ampoule by the barrier and the rubber diaphragm. In use, the ampoule is placed in the barrel of a hypodermic syringe, and is then manually advanced in the barrel toward the distal end of the syringe to cause the proximal end of the hypodermic needle of the syringe, which proximal end extends into the barrel of the syringe, to perforate the rubber diaphragm and communicate with the distal compartment of the ampoule. The distal end of the hypodermic needle is then inserted into the oral tissues of the patient.