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Nalex AC Side Effects

Generic Name: brompheniramine / codeine

Note: This document contains side effect information about brompheniramine / codeine. Some of the dosage forms listed on this page may not apply to the brand name Nalex AC.

For the Consumer

Applies to brompheniramine / codeine: oral syrup

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Like other narcotic medications, codeine can slow your breathing. Death may occur if breathing becomes too weak.

A person caring for you should seek emergency medical attention if you have slow breathing with long pauses, blue colored lips, or if you are hard to wake up.

Stop using brompheniramine and codeine and call your doctor at once if you have:

  • noisy breathing, sighing, shallow breathing;

  • a slow heart rate or weak pulse;

  • a light-headed feeling, like you might pass out;

  • easy bruising or bleeding;

  • painful or difficult urination;

  • confusion, hallucinations, ringing in your ears; or

  • a seizure (convulsions).

Serious side effects may be more likely in older adults and those who are overweight, malnourished, or debilitated.

Common side effects may include:

Side effects such as dry mouth, constipation, and confusion may be more likely in older adults.

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 brompheniramine / codeine: oral syrup

Nervous system

Nervous System side effects have included sedation, sleepiness, dizziness, disturbed coordination, fatigue, confusion, restlessness, excitation, nervousness, tremor, irritability, insomnia, euphoria, paresthesias, vertigo, tinnitus, acute labyrinthitis, hysteria, neuritis, and convulsions.[Ref]


Respiratory side effects have included thickening of bronchial secretions, dryness of mouth, nose, and throat, nasal stuffiness, tightness of the chest and wheezing.[Ref]


Gastrointestinal side effects have included epigastric distress, anorexia, nausea, vomiting, diarrhea, and constipation.[Ref]


Genitourinary side effects have included urinary frequency, difficult urination, urinary retention, and early menses.[Ref]


Hematologic side effects have included hemolytic anemia, thrombocytopenia, and agranulocytosis.[Ref]


Cardiovascular side effects have included hypotension, headache, palpitations, tachycardia, and extra systoles.[Ref]


Dermatologic side effects have included urticaria, photosensitivity, and pruritus.[Ref]


Hypersensitivity side effects have included drug rash and anaphylactic shock.[Ref]


Ocular side effects have included blurred vision and diplopia.[Ref]


General side effects have included excessive perspiration and chills.[Ref]


1. "Product Information. EndaCof-AC (brompheniramine-codeine)." Larken Laboratories Inc, Madison, MS.

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.

More about Nalex AC (brompheniramine / codeine)

Consumer resources

Other brands: EndaCof-AC

Other Formulations

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