Abstract: A stable, non-irritating composition and method for treating, without side effects, acute or chronic rhinosinusitis and its associated upper airway symptoms. The composition and treatment are useful for relieving the symptoms, and shortening the duration, of acute or chronic rhinosinusitis. The composition comprises a therapeutically effective solution having a pH of about 6.0, of ascorbic acid and caffeine, in combination with other soluble vitamins, natural ingredients and preservatives in a pharmaceutically acceptable carrier. The method includes the steps of preparing and administering the composition to the nasal membranes of a patient in the form of a nasal spray or drops.