Nasal Spray Oxymetazoline HCl 0.05% maximum strength, provides fast, powerful congestion relief for allergies and colds for up to 12 hours. The active ingredient is oxymetazoline hydrochloride 0.05%, nasal decongestant, soothes as it relieves and clears stuffy noses fast. This original nasal spray mist temporarily relieves nasal congestion and sinus congestion and pressure due to common cold, hay fever, and upper respiratory allergies.