Phenylephrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose).
Phenylephrine is used to treat nasal and sinus congestion, or congestion of the tubes that drain fluid from your inner ears, called the eustachian (yoo-STAY-shun) tubes.
Do not use phenylephrine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.
Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
phenylephrine and call your doctor at once if you have:
- fast, pounding, or uneven heartbeat;
- severe dizziness or anxiety;
- easy bruising or bleeding, unusual weakness, fever, chills, body aches, flu symptoms; or
- dangerously high blood pressure (severe headache, blurred vision, ringing in your ears, anxiety, confusion, chest pain, trouble breathing, uneven heart rate, seizure).
Common side effects
- loss of appetite;
- warmth, tingling, or redness under your skin;
- feeling restless or excited (especially in children);
- sleep problems (insomnia); or
- skin rash or itching.