Comparative Pharmacology
Head-to-head clinical analysis: ACTRON versus ALEVE PM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ACTRON versus ALEVE PM.
ACTRON vs ALEVE PM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Acetaminophen (paracetamol) is a non-opioid analgesic and antipyretic. Its mechanism is not fully understood but involves inhibition of cyclooxygenase (COX) enzymes in the central nervous system, reducing prostaglandin synthesis. It also modulates the endocannabinoid system and serotonergic pathways.
Diphenhydramine is a histamine H1 receptor antagonist that competes with histamine for binding at H1 receptor sites, reducing symptoms of allergic reactions and causing sedation. Naproxen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, decreasing synthesis of prostaglandins, which reduces pain and inflammation.
Oral: 400 mg every 4-6 hours as needed for pain; maximum 1200 mg/day.
1 tablet (220 mg naproxen sodium / 25 mg diphenhydramine HCl) orally at bedtime as needed. Maximum: 2 tablets in 24 hours.
None Documented
None Documented
Terminal elimination half-life 2-4 hours; prolonged to 6-12 hours in elderly or renal impairment (CrCl <30 mL/min).
Naproxen: 12-17 hours (mean 13.6 hours); sufficient for twice-daily dosing; prolonged in renal impairment. Diphenhydramine: 2.4-9.3 hours (mean 5.5 hours); longer in elderly, hepatic impairment.
Renal: 90% as unchanged drug; biliary/fecal: 10% as metabolites.
Naproxen: renal (95% as unchanged drug and metabolites, primarily as naproxen and 6-O-desmethyl naproxen). Diphenhydramine: renal (50-60% as unchanged drug and metabolites, primarily as diphenhydramine and nor diphenhydramine); small amounts in feces.
Category C
Category C
NSAID
NSAID/Antihistamine Combination