An antihistaminic effective amount of a) one or more histamine H1 receptor antagonists and b) one or more histamine H3 receptor antagonists having Ki value no greater than 200 nanoMolar in a guinea pig brain membrane assay are used in the manufacture of a medicament for relieving symptoms of rhinitis in a mammal. The histamine H1 receptor antagonists and the histamine H3 receptor antagonists are maintained simultaneously in the circulatory system and the amount of the histamine H3 receptor antagonist is sufficient to provide a nasal decongestant effect.
use of a combination of a histamine H1 receptor antagonist and a histamine H3 receptor antagonist to treat upper airway allergic responses