A multi-function oxygen mask for the administration of a gas such as oxygen comprising, in combination: a mask body forming an internal cavity configured to cover a nose and a mouth of a patient, said mask body including an upper portion, a lower portion, a peripheral edge, forming a sealing surface, a nasal chamber having an upper portion and a lower portion, an access aperture adjacent to said lower portion of said mask body, an upper sealing edge adjacent to said upper portion of said mask body and a gas delivery adapter aperture adjacent to said lower portion of said nasal chamber; a gas delivery adapter including a first end, a second end, an oxygen supply port adjacent to said first end and radially extending outward from said gas delivery adapter, a meter-dose inhaler port adjacent to said first end and radially extending outward from said gas delivery adapter and a nebulizer port adjacent to said second end, said first end of said gas delivery adapter coupled to said gas delivery adapter aperture, wherein said oxygen supply port has an external inlet portion, an outlet portion positioned within a volumetric space of said gas delivery adapter and a diverter member adjacent to said outlet portion, said diverter member configured to direct a flow towards said first end of said gas delivery adapter, characterized in that said diverter member extends from an inner surface of the gas delivery adapter towards a center of the gas delivery adapter and then towards said first end of the gas delivery adapter thereby directing a flow from the outlet portion towards said first end of said gas delivery adapter, and wherein the diverter member is integrally formed within the gas delivery adapter; and a meter-dose inhaler insert within said meter-dose inhaler port, said meter-dose inhaler insert having a discharge port positioned within said volumetric space and configured to direct a flow towards said first end of said gas delivery adapter. a mask body forming an internal cavity configured to cover a nose and a mouth of a patient, said mask body including an upper portion, a lower portion, a peripheral edge, forming a sealing surface, a nasal chamber having an upper portion and a lower portion, an access aperture adjacent to said lower portion of said mask body, an upper sealing edge adjacent to said upper portion of said mask body and a gas delivery adapter aperture adjacent to said lower portion of said nasal chamber; a gas delivery adapter including a first end, a second end, an oxygen supply port adjacent to said first end and radially extending outward from said gas delivery adapter, a meter-dose inhaler port adjacent to said first end and radially extending outward from said gas delivery adapter and a nebulizer port adjacent to said second end, said first end of said gas delivery adapter coupled to said gas delivery adapter aperture, wherein said oxygen supply port has an external inlet portion, an outlet portion positioned within a volumetric space of said gas delivery adapter and a diverter member adjacent to said outlet portion, said diverter member configured to direct a flow towards said first end of said gas delivery adapter, characterized in that said diverter member extends from an inner surface of the gas delivery adapter towards a center of the gas delivery adapter and then towards said first end of the gas delivery adapter thereby directing a flow from the outlet portion towards said first end of said gas delivery adapter, and wherein the diverter member is integrally formed within the gas delivery adapter; and a meter-dose inhaler insert within said meter-dose inhaler port, said meter-dose inhaler insert having a discharge port positioned within said volumetric space and configured to direct a flow towards said first end of said gas delivery adapter.