Comparative Pharmacology
Head-to-head clinical analysis: ACETAMINOPHEN AND IBUPROFEN versus NAPROSYN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ACETAMINOPHEN AND IBUPROFEN versus NAPROSYN.
ACETAMINOPHEN AND IBUPROFEN vs NAPROSYN
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.
Nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2) enzymes, thereby reducing prostaglandin synthesis. This results in decreased inflammation, pain, and fever.
Oral: Acetaminophen 325 mg and ibuprofen 200 mg, 1-2 tablets every 6 hours as needed, not exceeding 6 tablets/24 hours.
250-500 mg orally twice daily; maximum 1500 mg/day. For extended-release: 750-1000 mg orally once daily.
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 12-17 hours. This long half-life allows twice-daily dosing, but may lead to drug accumulation in elderly or renally impaired patients.
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 excretion of conjugated metabolites accounts for approximately 95% of a dose, with 1-2% as unchanged naproxen. Fecal excretion is minimal (<5%).
Category D/X
Category C
NSAID
NSAID