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Ornex Maximum Strength Side Effects

Generic name: acetaminophen / pseudoephedrine

Note: This document contains side effect information about acetaminophen / pseudoephedrine. Some dosage forms listed on this page may not apply to the brand name Ornex Maximum Strength.

Applies to acetaminophen / pseudoephedrine: oral tablet.


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.

You should not use this medicine if you have untreated or uncontrolled diseases such as glaucoma, asthma or COPD, high blood pressure, heart disease, coronary artery disease, or overactive thyroid.

Avoid drinking alcohol. It may increase your risk of liver damage while taking acetaminophen.

Do not use cold 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.

Ask a doctor or pharmacist before using any other cold, allergy, pain, or sleep medication. Acetaminophen (sometimes abbreviated as APAP) is contained in many combination medicines. Taking certain products together can cause you to get too much acetaminophen which can lead to a fatal overdose. Check the label to see if a medicine contains acetaminophen or APAP.

Get emergency medical help if you have any of these signs of an allergic reaction while taking acetaminophen/pseudoephedrine: 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:

  • fast, slow, or uneven heart rate;

  • confusion, hallucinations;

  • tremor, seizure (convulsions);

  • little or no urinating;

  • nausea, 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, seizure).

Common side effects may include:

  • dizziness, weakness;

  • mild headache;

  • mild nausea, diarrhea, upset stomach;

  • runny nose;

  • feeling nervous, restless, or anxious; or

  • sleep problems (insomnia).

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 / pseudoephedrine: oral capsule, oral liquid, oral tablet, oral tablet chewable.


Frequency not reported: Tachycardia, palpitations, other cardiac dysrhythmias, hypertension[Ref]


Frequency not reported: Hypersensitivity reactions (including cross-reactivity with other sympathomimetics)[Ref]

Nervous system

Frequency not reported: Headache, tremor[Ref]


Frequency not reported: Irritability, anxiety, excitability, insomnia, hallucinations (particularly in children), paranoid delusions, sleep disturbance[Ref]


Frequency not reported: Nausea, vomiting[Ref]


Frequency not reported: Skin reaction (including rash)[Ref]


Frequency not reported: Urinary retention[Ref]


1. Cerner Multum, Inc. UK Summary of Product Characteristics.

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.