Comparative Pharmacology
Head-to-head clinical analysis: ALEVE PM versus AMBENYL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ALEVE PM versus AMBENYL.
ALEVE PM vs AMBENYL
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.
AMBENYL is a combination product containing codeine (opioid agonist) and bromodiphenhydramine (antihistamine). Codeine binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception; bromodiphenhydramine antagonizes histamine H1 receptors, producing antitussive and sedative effects.
1 tablet (220 mg naproxen sodium / 25 mg diphenhydramine HCl) orally at bedtime as needed. Maximum: 2 tablets in 24 hours.
Each 5 mL contains codeine phosphate 10 mg and diphenhydramine hydrochloride 12.5 mg. Adults: 10 mL (2 teaspoonfuls) orally every 4-6 hours as needed; maximum 40 mL per day.
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.
Codeine: 2.5-3.5 h (terminal) with CYP2D6 poor metabolizers up to 6 h. Guaifenesin: 1-2 h.
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: 60% unchanged codeine, 20% codeine-6-glucuronide; biliary/fecal: 20% as metabolites. Guaifenesin: renal 95% as unchanged drug and metabolites.
Category C
Category C
NSAID/Antihistamine Combination
Antitussive/Antihistamine Combination