Comparative Pharmacology
Head-to-head clinical analysis: ERGOMETRINE versus METHERGINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ERGOMETRINE versus METHERGINE.
Ergometrine / Methylergonovine vs METHERGINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Ergometrine and methylergonovine are ergot alkaloids that act as partial agonists at alpha-adrenergic, dopaminergic, and serotonergic (5-HT2) receptors. Their primary uterotonic effect is mediated by stimulation of 5-HT2 receptors in uterine smooth muscle, leading to sustained contractions and vasoconstriction.
Methylergonovine is an ergot alkaloid that acts as a partial agonist at α-adrenergic receptors in the uterine smooth muscle, causing sustained contractions. It also exhibits serotonergic (5-HT2) and dopaminergic activity.
0.2 mg intramuscularly or intravenously, repeated every 2-4 hours as needed, up to 5 doses total. Maximum single dose: 0.5 mg. Maximum total dose: 1 mg.
0.2 mg intramuscularly or intravenously after delivery of placenta and every 2-4 hours as needed, up to a maximum of 5 doses.
None Documented
None Documented
30-120 min (biphasic: initial 10 min, terminal 30-120 min); clinical context: short half-life allows repeated dosing for postpartum hemorrhage but requires monitoring for accumulation
Terminal elimination half-life is approximately 2–3 hours in healthy adults; prolonged in hepatic impairment.
Renal (20% unchanged), biliary/fecal (35% as metabolites and parent compound)
Primarily hepatic metabolism; less than 1% excreted unchanged in urine. Biliary/fecal excretion accounts for ~80% of metabolites.
Category C
Category C
Ergot Alkaloid Uterotonic
Ergot Alkaloid Uterotonic