Comparative Pharmacology
Head-to-head clinical analysis: ALEVE PM versus VOLTAREN XR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ALEVE PM versus VOLTAREN XR.
ALEVE PM vs VOLTAREN-XR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX-1 and COX-2), reducing prostaglandin synthesis. This leads to anti-inflammatory, analgesic, and antipyretic effects.
1 tablet (220 mg naproxen sodium / 25 mg diphenhydramine HCl) orally at bedtime as needed. Maximum: 2 tablets in 24 hours.
100 mg orally once daily, extended-release formulation. Maximum 150 mg/day (divided as 75 mg twice daily or 100 mg once daily).
None Documented
None Documented
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.
The terminal elimination half-life is approximately 2 hours. The extended-release formulation (XR) does not alter the half-life; it maintains prolonged therapeutic plasma concentrations with twice-daily dosing.
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.
Approximately 65% of a dose is excreted renally as unchanged drug and metabolites (primarily as glucuronide conjugates); about 35% is eliminated via bile in feces.
Category C
Category C
NSAID/Antihistamine Combination
NSAID