Refined BAC nasal drops relieve stuffy noses (blocked noses). The concentration of BAC in nasal sprays, drops, and ointments is usually ranges from 0.005% to 0.2%, other concentration might be used . Moisturizes and loosens nasal mucus to relieve congestion quickly. Sodium chloride and benzalkonium chloride nasal drops moisturize the nose . This helps treat a stuffy nose from a cold or allergies . Using nasal decongestants for allergic rhinitis for a long time can cause "rebound swelling" and more congestion . The preservative BAC in most decongestant sprays can worsen allergic rhinitis and cause toxic reactions in the nose, eyes, ears, and lungs .