Comparative Pharmacology
Head-to-head clinical analysis: EMETE CON versus PROMETHAZINE W CODEINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EMETE CON versus PROMETHAZINE W CODEINE.
EMETE-CON vs PROMETHAZINE W/ CODEINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antiemetic; dopaminergic antagonist at D2 receptors in the chemoreceptor trigger zone; also exhibits anticholinergic and antihistaminic properties.
Codeine is a prodrug converted to morphine, a mu-opioid receptor agonist, which inhibits nociceptive transmission; promethazine is a phenothiazine derivative with H1-receptor antagonism, anticholinergic, and antiemetic effects.
12.5 mg intravenously over 30 seconds as a single dose; may repeat once after 1 hour if necessary.
10 mL (1 mg codeine, 6.25 mg promethazine per 5 mL) orally every 4-6 hours as needed for cough. Maximum: 60 mL per day. Do not exceed 5 days.
None Documented
None Documented
Terminal elimination half-life is 8-12 hours in adults with normal renal and hepatic function; may extend to 15-20 hours in elderly or patients with hepatic impairment.
Promethazine: 10-19 hours (terminal). Codeine: 2.5-3.5 hours (terminal); prolonged in renal impairment.
Primarily hepatic metabolism (CYP2D6, CYP3A4) with <5% excreted unchanged in urine. Biliary/fecal excretion accounts for approximately 60-70% of metabolites, with renal elimination of metabolites constituting 25-35%.
Promethazine: renal (70% as metabolites, <1% unchanged), fecal (20-30%). Codeine: renal (90%, of which 5-10% unchanged, rest as metabolites), fecal (minor).
Category C
Category A/B
Antiemetic
Antihistamine / Antiemetic