Comparative Pharmacology
Head-to-head clinical analysis: ALEVE PM versus PREFRIN A.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ALEVE PM versus PREFRIN A.
ALEVE PM vs PREFRIN-A
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.
PREFRIN-A contains phenylephrine, an alpha-1 adrenergic receptor agonist, and acetaminophen, a centrally acting analgesic and antipyretic. Phenylephrine causes vasoconstriction in nasal mucosa, reducing congestion. Acetaminophen inhibits cyclooxygenase (COX) enzymes in the brain, reducing prostaglandin synthesis.
1 tablet (220 mg naproxen sodium / 25 mg diphenhydramine HCl) orally at bedtime as needed. Maximum: 2 tablets in 24 hours.
1 drop in each affected eye every 3-4 hours as needed, not to exceed 4 times 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.
Terminal elimination half-life: 2-4 hours in adults; 6-12 hours in neonates and infants due to immature hepatic metabolism.
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.
Renal: 70-80% as unchanged drug and metabolites; biliary/fecal: 20-30% as metabolites.
Category C
Category C
NSAID/Antihistamine Combination
Ophthalmic Decongestant/Antihistamine Combination