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Codeine / Diphenhydramine / Phenylephrine Side Effects

Applies to codeine/diphenhydramine/phenylephrine: oral syrup.

Important warnings This medicine can cause some serious health issues

You should not use this medicine if you have bladder obstruction or urination problems, uncontrolled high blood pressure, severe coronary artery disease, narrow-angle glaucoma, a stomach ulcer, or uncontrolled asthma.

Do not use this medicine if you have taken 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, and tranylcypromine.

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

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

Common side effects may include:

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 codeine / diphenhydramine / phenylephrine: oral syrup.

Nervous system

Nervous system side effects have included drowsiness, dizziness, headache, nervousness, restlessness, impairment of mental performance, weakness, mental clouding, lethargy, anxiety, convulsions, CNS depression, tremor, and insomnia.[Ref]

Psychiatric

Psychiatric side effects have included fear, dysphoria, psychic dependence, feeling of well-being, confusion, and mood changes.[Ref]

Cardiovascular

Cardiovascular side effects have included tachycardia, palpitations, arrhythmias, change in heart rate, and cardiovascular collapse with hypotension.[Ref]

Gastrointestinal

Gastrointestinal side effects have included loss of appetite, nausea, constipation, dry mouth, anorexia, vomiting, and heartburn.[Ref]

Genitourinary

Genitourinary side effects have included dysuria, polyuria, ureteral spasm, spasm of vesical sphincters, urinary disturbances, and urinary retention.[Ref]

Respiratory

Respiratory side effects have included respiratory difficulty and respiratory depression.[Ref]

Dermatologic

Dermatologic side effects have included increased sweating, pallor, skin hash, hives, swelling of face, and dermatitis.[Ref]

Ocular

Ocular side effects have included blurring of vision and visual disturbances.[Ref]

References

1. (2008) "Product Information. Endal CD (codeine / diphenhydramine / phenylephrine)." Tiber Laboratories

Further information

Codeine/diphenhydramine/phenylephrine side effects can vary depending on the individual. 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.