Comparative Pharmacology
Head-to-head clinical analysis: MAXOLON versus PROMETHAZINE HYDROCHLORIDE PHENYLEPHRINE HYDROCHLORIDE W CODEINE PHOSPHATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: MAXOLON versus PROMETHAZINE HYDROCHLORIDE PHENYLEPHRINE HYDROCHLORIDE W CODEINE PHOSPHATE.
MAXOLON vs PROMETHAZINE HYDROCHLORIDE,PHENYLEPHRINE HYDROCHLORIDE W/CODEINE PHOSPHATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Metoclopramide, the active ingredient in MAXOLON, is a dopamine D2 receptor antagonist and also enhances the response to acetylcholine at muscarinic receptors in the gastrointestinal tract, leading to increased gastric motility and accelerated gastric emptying. It also has antiemetic effects by blocking dopamine receptors in the chemoreceptor trigger zone (CTZ).
Promethazine is a phenothiazine derivative that acts as a histamine H1 receptor antagonist, sedative, and antiemetic via central dopamine D2 and muscarinic M1 receptor blockade. Phenylephrine is a sympathomimetic amine that acts as a selective α1-adrenergic receptor agonist, causing vasoconstriction. Codeine is an opioid agonist at mu-opioid receptors, producing analgesia and antitussive effects, partly after O-demethylation to morphine.
10 mg orally, intramuscularly, or intravenously three to four times daily. Maximum daily dose: 30 mg or 0.5 mg/kg.
Each 5 mL of oral solution contains promethazine hydrochloride 6.25 mg, phenylephrine hydrochloride 5 mg, and codeine phosphate 10 mg. Adult dose: 5 mL every 4 to 6 hours as needed. Maximum 30 mL per day.
None Documented
None Documented
5-6 hours in adults with normal renal function; prolonged to 15-20 hours in severe renal impairment (CrCl <10 mL/min).
Promethazine: 9-16 h (adults); prolonged in hepatic impairment. Phenylephrine: 2-3 h (oral); 5-10 min (IV due to rapid redistribution). Codeine: 2.5-3.5 h; active metabolites (morphine) 2-3 h.
Renal: 85-95% as unchanged drug and metabolites; biliary/fecal: <5%.
Promethazine: ~70% renal as metabolites, minor biliary/fecal. Phenylephrine: ~86-96% renal as metabolites (sulfate and glucuronide conjugates). Codeine: ~90% renal, primarily as morphine and norcodeine conjugates; 5-10% unchanged. Fecal excretion minimal.
Category C
Category A/B
Antiemetic
Antihistamine / Antiemetic