Comparative Pharmacology
Head-to-head clinical analysis: DEMEROL versus MEPERGAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DEMEROL versus MEPERGAN.
DEMEROL vs MEPERGAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Meperidine is an opioid agonist that binds to mu-opioid receptors in the central nervous system, mimicking endogenous endorphins to produce analgesia, sedation, and euphoria. It also has additional weak actions at kappa and delta receptors.
Meperidine is a synthetic opioid agonist that binds to mu-opioid receptors in the central nervous system, mimicking endogenous endorphins to produce analgesia. Promethazine is a phenothiazine antipsychotic that antagonizes histamine H1, dopamine D2, muscarinic acetylcholine, and alpha-adrenergic receptors, providing sedation and antiemetic effects.
50-150 mg IM, IV, or SC every 3-4 hours as needed for pain; oral 50-150 mg every 3-4 hours.
Meperidine 50-100 mg and promethazine 25-50 mg IM/IV every 3-4 hours as needed. Maximum meperidine dose: 600 mg/day.
None Documented
None Documented
2.5-4 hours; prolonged in hepatic impairment (7-11 hours) and elderly.
Meperidine: 3-4 hours (terminal; increased in hepatic impairment). Promethazine: 9-16 hours (terminal; prolonged in elderly).
Renal (90% as metabolites and unchanged drug; ~5% unchanged) and biliary/fecal (minor).
Renal elimination of metabolites (meperidine: ~90% as metabolites, <5% unchanged; promethazine: ~70-80% as metabolites, <1% unchanged). Biliary/fecal excretion is minimal (<10% for both).
Category C
Category C
Opioid Analgesic
Opioid Analgesic/Antiemetic Combination