Comparative Pharmacology
Head-to-head clinical analysis: ACETAMINOPHEN AND IBUPROFEN versus ANAPROX DS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ACETAMINOPHEN AND IBUPROFEN versus ANAPROX DS.
ACETAMINOPHEN AND IBUPROFEN vs ANAPROX DS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Acetaminophen is a centrally acting analgesic and antipyretic whose exact mechanism is not fully understood, but is thought to involve inhibition of cyclooxygenase (COX) in the brain and modulation of cannabinoid receptors. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that non-selectively inhibits COX-1 and COX-2, reducing prostaglandin synthesis.
Naproxen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2) enzymes, reducing prostaglandin synthesis.
Oral: Acetaminophen 325 mg and ibuprofen 200 mg, 1-2 tablets every 6 hours as needed, not exceeding 6 tablets/24 hours.
550 mg orally every 8 to 12 hours; maximum 1375 mg/day.
None Documented
None Documented
Acetaminophen: 2-3 hours (normal hepatic function). Ibuprofen: 2-4 hours (immediate-release); prolonged in overdose or hepatic impairment.
Terminal elimination half-life is approximately 12–17 hours (mean ~14 hours), allowing twice-daily dosing. Steady-state is achieved after 4–5 doses.
Acetaminophen: renal excretion of metabolites (glucuronide 55%, sulfate 30%, cysteine/mercapturate <10%); <5% unchanged. Ibuprofen: renal excretion of metabolites (conjugates) 90%; <10% unchanged; minor biliary/fecal.
Renal elimination of naproxen and its metabolites accounts for approximately 95% of the dose, with about 60% as unchanged drug and 40% as conjugated or hydroxylated metabolites. Biliary/fecal excretion is negligible (<5%).
Category D/X
Category C
NSAID
NSAID