Comparative Pharmacology
Head-to-head clinical analysis: MEPERIDINE HYDROCHLORIDE versus WESTADONE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: MEPERIDINE HYDROCHLORIDE versus WESTADONE.
MEPERIDINE HYDROCHLORIDE vs WESTADONE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Meperidine is a synthetic opioid agonist that binds to mu-opioid receptors in the central nervous system, mimicking endogenous endorphins to produce analgesia. It also has weak serotonergic activity.
Mu-opioid receptor agonist; also acts as an NMDA receptor antagonist and inhibits serotonin and norepinephrine reuptake.
50-150 mg orally or intramuscularly every 3-4 hours as needed for pain. Maximum single dose: 150 mg. Maximum daily dose: 600 mg.
Oral: 2.5-10 mg every 4-6 hours as needed for pain; maximum 40 mg per day.
None Documented
None Documented
3-4 hours in normal renal function; prolonged to >12 hours in hepatic impairment (cirrhosis) or renal failure (normeperidine accumulates)
Terminal elimination half-life: 15-60 hours (mean ~24 hours). Clinical context: Prolonged half-life supports once-daily dosing in opioid maintenance; accumulation occurs with repeated dosing due to long half-life.
Renal: 70-80% as metabolites (normeperidine ~20%, meperidinic acid ~50%) and <5% unchanged; biliary/fecal: <10%
Primarily renal (40-50% as unchanged methadone and its metabolites, 15-20% as metadone-N-oxide), biliary/fecal (5-10%).
Category D/X
Category C
Opioid Agonist
Opioid Agonist