Comparative Pharmacology
Head-to-head clinical analysis: PROMETH FORTIS versus PROMETHAZINE HYDROCHLORIDE PHENYLEPHRINE HYDROCHLORIDE W CODEINE PHOSPHATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PROMETH FORTIS versus PROMETHAZINE HYDROCHLORIDE PHENYLEPHRINE HYDROCHLORIDE W CODEINE PHOSPHATE.
PROMETH FORTIS vs PROMETHAZINE HYDROCHLORIDE,PHENYLEPHRINE HYDROCHLORIDE W/CODEINE PHOSPHATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Promethazine is a phenothiazine derivative that acts as a histamine H1 receptor antagonist, with additional anticholinergic, antiemetic, and sedative properties. It blocks histamine at H1 receptors, reducing allergic symptoms and motion sickness, and exerts antiemetic effects by blocking dopamine D2 receptors in the chemoreceptor trigger zone.
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.
Adults: 12.5-25 mg intramuscular or intravenous every 4-6 hours as needed for nausea. For severe nausea up to 50 mg IM/IV. Maximum single dose 50 mg, maximum daily dose 200 mg.
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
Terminal elimination half-life: 9–16 hours (mean ~12 hours). In children and elderly, half-life may be prolonged (up to 20 hours).
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.
Primarily renal as inactive metabolites; <1% excreted unchanged. Total elimination: renal ~70%, fecal ~30%.
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
Antihistamine
Antihistamine / Antiemetic