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Acetaminophen / caffeine / phenyltoloxamine Side Effects

Applies to acetaminophen / caffeine / phenyltoloxamine: oral capsule


Cardiovascular side effects have included palpitations, hypotension, and cardiac stimulation.[Ref]


Gastrointestinal side effects have included epigastric distress, diarrhea, intestinal cramps, nausea, xerostomia, and dryness of mouth, throat, and nose.[Ref]


Dermatologic side effects have included urticaria and rash. Acetaminophen has been associated with a risk of rare but potentially fatal serious skin reactions know as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP).[Ref]


Hypersensitivity side effects have included allergic reactions.[Ref]


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


Musculoskeletal side effects have included muscular weakness.[Ref]


Genitourinary side effects have included urinary retention.[Ref]

Nervous system

Nervous system side effects have included dizziness, drowsiness, disturbed coordination, inability to concentrate, insomnia, tremors, nervousness, convulsions, irritability, and dependence.[Ref]


Ocular side effects have included blurred vision.[Ref]


Renal side effects have included nephrotoxicity.[Ref]


Metabolic side effects have included hyperglycemia.[Ref]


1. "Product Information. Flextra (APAP/caffeine/phenyltoloxamine)." Poly Pharmaceuticals Inc, Quitman, MS.

Not all side effects for acetaminophen / caffeine / phenyltoloxamine may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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