Do not use phenylephrine for longer than 3 to 5 days. Longer use could damage your nasal tissue and lead to chronic congestion. If your symptoms do not improve, see your doctor. Do not use more of this medication than is recommended on the package or by your doctor.
Phenylephrine is a decongestant.
The nasal formulation acts directly on the blood vessels in your nasal tissues. Constriction of the blood vessels in your nose and sinuses leads to drainage of these areas and decreases congestion. Phenylephrine nasal is used to treat congestion associated with allergies, hay fever, sinus irritation, and the common cold. Phenylephrine nasal may also be used for purposes other than those listed in this medication guide. A very dangerous drug interaction with serious side effects could occur.