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Acetaminophen / pheniramine / phenylephrine Side Effects

Medically reviewed by Last updated on Nov 23, 2021.

Applies to acetaminophen / pheniramine / phenylephrine: oral powder for reconstitution.


Ask a doctor before taking medicine that contains acetaminophen if you have ever had liver disease, or if you drink more than 3 alcoholic beverages per day.

Do not use cold or allergy medicine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include furazolidone, isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

In rare cases, acetaminophen may cause a severe skin reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling.

Do not take more of this medication than is recommended. An overdose of acetaminophen can damage your liver or cause death.

Get emergency medical help if you have any of these signs of an allergic reaction while taking acetaminophen/pheniramine/phenylephrine: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

In rare cases, acetaminophen may cause a severe skin reaction that can be fatal. This could occur even if you have taken acetaminophen in the past and had no reaction. Stop taking this medicine and call your doctor right away if you have skin redness or a rash that spreads and causes blistering and peeling. If you have this type of reaction, you should never again take any medicine that contains acetaminophen.

Stop using the medicine and call your doctor at once if you have:

  • chest pain, rapid pulse, fast or uneven heart rate;

  • confusion, hallucinations, tremor, severe dizziness or anxiety;

  • slow, shallow breathing;

  • little or no urinating;

  • easy bruising or bleeding, unusual weakness;

  • nausea, pain in your upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or

  • dangerously high blood pressure (severe headache, blurred vision, buzzing in your ears, anxiety, confusion, chest pain, shortness of breath, uneven heartbeats, seizure).

Common side effects may include:

  • dryness of the eyes, nose, and mouth;

  • blurred vision;

  • dizziness, drowsiness, problems with memory or concentration;

  • ringing in your ears;

  • feeling restless or irritable; or

  • mild nausea, stomach pain, constipation.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

For Healthcare Professionals

Applies to acetaminophen/pheniramine/phenylephrine: oral powder for reconstitution.


Frequency not reported: Hepatotoxic action and nephrotoxicity with prolonged high dose use[Ref]


Frequency not reported: Palpitations, blood pressure increase[Ref]

Nervous system

Frequency not reported: Hyperexcitability, drowsiness, dizziness, accommodative palsy, sleep disorder[Ref]


Frequency not reported: Changes in blood count with prolonged high dose use[Ref]


Frequency not reported: Possible allergic reactions (skin rash, pruritus, hives, angioedema)[Ref]


Frequency not reported: Nausea, vomiting, stomach pain, dry mouth[Ref]


Frequency not reported: Urinary retention[Ref]


Frequency not reported: Increase in intraocular pressure[Ref]


1. "Product Information. Theraflu Cold and Sore Throat (acetaminophen / pheniramine / phenylephrine)." Novartis Consumer Health

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.