A method and an apparatus for applying an anesthetic include an elongated tubular housing having an upper end, a substantially hollow interior, and a lower end having an injection needle extending therefrom. A first chamber is formed within the housing interior for holding an anesthetic cartridge therein. A second chamber receives a cannister containing an endothermic gas that rapidly absorbs heat when released to the atmosphere. The cartridge is penetrated by a plunger that forces the anesthetic through the injection needle. A depressible trigger propels the gas through an outlet nozzle that is oriented to project a stream of gas along a delivery axis that intersects a delivery axis of the needle therefore, the gas and anesthetic can be successively delivered to an injection site with minimal repositioning of the housing. Accordingly, a dental practitioner can initially disperse the endothermic gas onto the injection site to minimize any pain and discomfort associated with an injection. Subsequently, the practitioner inserts the needle into the deadened site and injects the anesthetic.
