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Alka-Seltzer Plus Severe Sinus Congestion & Cough (Night Formula) Side Effects

Generic Name: acetaminophen / dextromethorphan / doxylamine / phenylephrine

Note: This page contains information about the side effects of acetaminophen / dextromethorphan / doxylamine / phenylephrine. Some of the dosage forms included on this document may not apply to the brand name Alka-Seltzer Plus Severe Sinus Congestion & Cough (Night Formula).

For the Consumer

Applies to acetaminophen / dextromethorphan / doxylamine / phenylephrine: liquid

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

Dizziness; drowsiness; dry mouth, nose, or throat; headache; nausea; nervousness; trouble sleeping.

Seek medical attention right away if any of these SEVERE side effects occur while taking acetaminophen / dextromethorphan / doxylamine / phenylephrine:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chest pain; dark urine; difficulty urinating or inability to urinate; fast or irregular heartbeat; hallucinations; mental or mood changes; pale stools; seizures; severe nervousness, drowsiness, or trouble sleeping; severe or persistent dizziness, lightheadedness, or headache; severe or persistent stomach pain, nausea, or vomiting; tremor; unusual fatigue; vision changes; yellowing of the skin or eyes.

For Healthcare Professionals

Applies to acetaminophen / dextromethorphan / doxylamine / phenylephrine: oral capsule, oral liquid, oral tablet, oral tablet effervescent


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


Dermatologic side effects associated with acetaminophen includes the risk of rare but potentially fatal serious skin reactions known as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP).


Gastrointestinal side effects have included nausea and vomiting.[Ref]


Genitourinary side effects have included dysuria.[Ref]


General side effects have included pallor and weakness.[Ref]


Hypersensitivity side effects have included rare reports of fixed-drug eruptions.[Ref]

Nervous system

Nervous system side effects have included marked drowsiness and excitability.[Ref]


Psychiatric side effects have included hallucinations, fear, and anxiety.[Ref]


1. "Product Information. Alka-Seltzer Plus Night-Time Cold (APAP/dextromethorphan/doxylamine/PE)." Bayer Pharmaceutical Inc, West Haven, CT.

Not all side effects for Alka-Seltzer Plus Severe Sinus Congestion & Cough (Night Formula) 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 Alka-Seltzer Plus Severe Sinus Congestion & Cough (Night Formula) (acetaminophen / dextromethorphan / doxylamine / phenylephrine)

Consumer resources

Other brands: Vicks NyQuil Severe Cold & Flu, Tylenol Cold Multi-Symptom Nighttime Liquid, Delsym Night Time Multi-Symptom

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