Abstract: A highly portable means for warming therapeutic gas to be administered to a patient which may also humidify the therapeutic gas. The apparatus includes means for passing the therapeutic gas through an area heated by a chemical reaction which requires no outside energy source. The heated area may comprise a liquid such as water which may optionally contain other therapeutic substances, resulting in both heating and humidifying of the therapeutic gas. The chemical heating means involves mixing two or more chemicals such as a liquid chemical and a dry chemical or atmospheric air and a dry chemical to produce an exothermic reaction. The apparatus is highly portable and may be carried, for instance, in ambulances, boats, aircraft, etc., as well as at medical facilities such as hospitals. The apparatus is lightweight, cheap to construct and economically disposable after use, thus avoiding the possibility of cross-contamination and avoiding any need for cleaning.