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Chlorpheniramine / methscopolamine / phenylephrine / pseudoephedrine Side Effects

For the Consumer

Applies to chlorpheniramine / methscopolamine / phenylephrine / pseudoephedrine: sustained-release tablets

Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Blurred vision; dizziness; drowsiness; dry mouth, nose, or throat; excitability or irritability (especially in children); headache; lack of energy; lightheadedness; nausea; nervousness; trouble sleeping.

Seek medical attention right away if any of these SEVERE side effects occur while taking chlorpheniramine / methscopolamine / phenylephrine / pseudoephedrine:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); fast or irregular heartbeat; flushing; hallucinations; mental or mood changes (eg, anxiety); seizures; severe or persistent drowsiness or dizziness; tremor; trouble urinating; unusual tiredness or weakness.

For Healthcare Professionals

Applies to chlorpheniramine / methscopolamine / phenylephrine / pseudoephedrine: oral kit


Cardiovascular side effects have included tachycardia, palpitations, flushing, arrhythmias, and cardiovascular collapse with hypotension.[Ref]

Nervous system

Nervous system side effects have included lassitude, drowsiness, giddiness, increased irritability or excitement, headache, fear, anxiety, nervousness,dizziness, restlessness, tremor, weakness, insomnia, hallucinations, convulsions, and CNS depression.[Ref]


Ocular side effects have included blurred vision.[Ref]


Gastrointestinal side effects have included nausea and excessive dryness of the nose, throat, and mouth.[Ref]


Respiratory side effects have included respiratory difficulty.[Ref]


Genitourinary side effects have included dysuria and urinary retention in patients with prostatic hypertrophy.[Ref]


1. "Product Information. AlleRx Dose Pack (chlorpheniramine/methscopolamine/PE/PSE)." Cornerstone BioPharma Inc, Cary, NC.

Not all side effects for chlorpheniramine / methscopolamine / phenylephrine / pseudoephedrine may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

More about chlorpheniramine/methscopolamine/phenylephrine/pseudoephedrine

Consumer resources

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