A new over-the-counter medicine that officials for Chattanooga-based Chattem Inc. believe can be a blockbuster offering for the company has hit store shelves.

"Now that Nasacort Allergy 24HR is available over-the-counter, the millions of people who suffer from seasonal and year-round allergies have easier access to the gold standard treatment for nasal allergy symptoms," said Chattem Chief Executive Zan Guerry in a statement.

Nasacort received approval from the U.S. Food and Drug Administration to switch from prescription to OTC in October 2013.

Chattem, the U.S. consumer health care division of Paris-based Sanofi, said Nasacort works differently than other over-the-counter treatments to relieve the full range of nasal allergy symptoms, including nasal congestion, by stopping more of the chemical responses that cause those symptoms.