Mometasone furoate Nasal Spray is the generic version of Nasonex. It contains the same corticosteroid mometasone. When mometasone furoate is sprayed into the nose, it can help to relieve inflammation, sneezing, itching and a blocked up or runny nose. What is Mometasone furoate Nasal Spray used for? Hay fever and perennial rhinitis Mometasone furoate Nasal Spray is used to treat the symptoms of hay fever (also called seasonal allergic rhinitis) and perennial rhinitis in adults and children aged 3 and older. Mometasone furoate Nasal Spray reduces the swelling and irritation in your nose and thereby relieving sneezing, itching and a blocked-up or runny nose caused by hay fever or perennial rhinitis. It is recommended that you start using the nasal spray in advance of the hay fever season and continue to use it throughout.