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Flextra Side Effects

Generic name: acetaminophen / caffeine / phenyltoloxamine

Note: This document contains side effect information about acetaminophen / caffeine / phenyltoloxamine. Some dosage forms listed on this page may not apply to the brand name Flextra.

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]

More about Flextra (acetaminophen / caffeine / phenyltoloxamine)

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1. "Product Information. Flextra-DS (acetaminophen-phenyltoloxamine)." Poly Pharmaceuticals Inc

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.