Comparative Pharmacology
Head-to-head clinical analysis: DURAGESIC 75 versus MEPERGAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DURAGESIC 75 versus MEPERGAN.
DURAGESIC-75 vs MEPERGAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fentanyl is a potent opioid agonist primarily at the mu-opioid receptor, exerting its analgesic effects by mimicking endogenous endorphins and enkephalins to activate G-protein-coupled inwardly rectifying potassium channels, leading to hyperpolarization and reduced neuronal excitability in pain pathways.
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.
Adults: Apply one 75 mcg/hr transdermal patch every 72 hours. Start with lower dose in opioid-naive patients.
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
22-25 hours after removal of patch; increased in elderly, hepatic/renal impairment
Meperidine: 3-4 hours (terminal; increased in hepatic impairment). Promethazine: 9-16 hours (terminal; prolonged in elderly).
Renal (75% as metabolites, <10% unchanged), fecal (25%)
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