Apparatus, methods, and kits for treating symptoms associated with common ailments, such as headaches, rhinitis, asthma, epilepsy, nervous disorders and the like, are provided. The apparatus comprises dispensers for carbon dioxide and other therapeutic gases. The methods comprise delivering small volumes of these gases to patients in a manner where the gas infuses into a body region in order to bathe the mucous membranes therein. It has been found that even very short exposure of patients to small volumes and high concentrations of such gases can provide significant relief from symptoms.