Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
Ergometrine / Methylergonovine vs ERGOMAR
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
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.
Ergotamine acts as a partial agonist at serotonin 5-HT1B and 5-HT1D receptors, causing vasoconstriction of cranial blood vessels. It also inhibits norepinephrine reuptake and has alpha-adrenergic blocking activity.
Prevention and treatment of postpartum hemorrhage (FDA approved),Uterine atony (FDA approved),Ovarian hyperstimulation syndrome (off-label),Variceal bleeding (off-label),Migraine headache (off-label)
Abortive treatment of acute migraine headaches with or without aura,Cluster headache
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.
Ergotamine tartrate 1-2 mg sublingually or orally at onset of migraine, then 1-2 mg every 30 minutes as needed, maximum 6 mg per attack and 10 mg per week.
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 for ergotamine, but clinical effects may persist longer due to active metabolites (e.g., ergotamine's half-life is 2.4 hours; metabolites have half-lives up to 10 hours).
Primarily hepatic via CYP3A4; also undergoes first-pass metabolism. Metabolites are excreted in urine and bile.
Primarily hepatic via CYP3A4; minor contributions from CYP2D6. Undergoes extensive first-pass metabolism.
Renal (20% unchanged), biliary/fecal (35% as metabolites and parent compound)
Primarily hepatic metabolism with extensive biliary excretion; less than 5% excreted unchanged in urine. Fecal elimination accounts for approximately 30-40% of the dose as metabolites.
85-90% (primarily to albumin and α1-acid glycoprotein)
90-95% bound to plasma proteins, primarily albumin.
0.4-0.6 L/kg; clinical meaning: moderate tissue distribution, consistent with limited extravascular binding
Approximately 0.4 L/kg (16-18 L in adults), indicating moderate tissue distribution.
Oral: 20-40% (due to extensive first-pass metabolism); IM: ~80%
Sublingual: ~40-50%; Oral: <10% due to extensive first-pass metabolism; Rectal: ~25-30%.
No specific guidelines; use with caution in severe renal impairment (GFR <30 m L/min) due to risk of accumulation and hypertensive effects.
GFR > 30 m L/min: No adjustment. GFR 10-30 m L/min: Caution; reduce dose by 50%. GFR < 10 m L/min: Contraindicated.
Child-Pugh Class A: no adjustment. Child-Pugh Class B: reduce dose by 50% or extend interval. Child-Pugh Class C: avoid use.
Child-Pugh A: Caution; reduce dose by 50%. Child-Pugh B: Contraindicated. Child-Pugh C: Contraindicated.
0.1-0.2 mg intramuscularly or intravenously every 2-4 hours as needed; maximum single dose 0.2 mg. For postpartum hemorrhage, 0.2 mg IM/IV repeated every 2-4 hours, max 5 doses.
Not recommended for children under 12 years. Pediatric use not established; avoid use.
Use lowest effective dose due to increased sensitivity and higher risk of hypertension and coronary vasospasm; consider 0.1 mg initially and titrate cautiously.
Elderly patients are more sensitive to vasoconstriction; use lower initial dose (e.g., 1 mg) and monitor for adverse effects.
Concurrent use with potent CYP3A4 inhibitors (e.g., macrolide antibiotics, protease inhibitors, azole antifungals) may result in acute ergot toxicity (vasospasm, cerebral and peripheral ischemia). Contraindicated in pregnancy for induction of labor due to risk of uterine rupture and fetal harm.
Serious and/or life-threatening peripheral ischemia and vasospasm have been associated with the concomitant use of ergotamine with potent CYP3A4 inhibitors including protease inhibitors, macrolide antibiotics, and azole antifungals.
May cause hypertension, especially in patients with preeclampsia or hypertension. Use with caution in patients with sepsis, hepatic or renal impairment, coronary artery disease, or peripheral vascular disease. Avoid prolonged use. Monitor uterine tone and bleeding.
Risk of ischemic events (peripheral, cardiac, cerebral), fibrosis (retroperitoneal, pulmonary, cardiac), elderly patients (more sensitive to adverse effects), ergotism, drug interactions with CYP3A4 inhibitors, and prolonged use leading to medication-overuse headache.
Pregnancy (except for postpartum hemorrhage), hypertension, preeclampsia, eclampsia, coronary artery disease, peripheral vascular disease, Raynaud's phenomenon, sepsis, hypersensitivity to ergot alkaloids, concurrent use of potent CYP3A4 inhibitors.
Hypersensitivity to ergot alkaloids, peripheral vascular disease, coronary artery disease, uncontrolled hypertension, sepsis, hepatic or renal impairment, pregnancy, breastfeeding, concomitant use with potent CYP3A4 inhibitors, hemiplegic or basilar migraine.
No known food interactions.
Avoid grapefruit and grapefruit juice as they inhibit CYP3A4, increasing ergotamine levels and risk of toxicity. No other significant food interactions.
First trimester: Limited human data; animal studies show embryotoxicity and fetotoxicity at high doses due to uterotonic effects, but no structural malformations. Increased risk of spontaneous abortion from uterine hyperstimulation. Second trimester: Uterotonic effects may cause placental abruption, preterm labor, or fetal hypoxia. Third trimester: Contraindicated due to potent uterotonic activity; can cause uterine tetany, fetal distress, and stillbirth. Avoid during pregnancy unless for postpartum hemorrhage.
Ergotamine (ERGOMAR) is contraindicated in pregnancy due to its oxytocic properties and potential for uterine hyperstimulation, fetal hypoxia, and congenital anomalies. First trimester: Increased risk of spontaneous abortion and major malformations (e.g., limb defects, CNS abnormalities) based on case reports. Second and third trimesters: Uterine hypertonicity and decreased placental perfusion leading to fetal distress, preterm labor, and low birth weight. Use only if benefit outweighs risk and no alternative; avoid in all trimesters.
Ergometrine and methylergonovine are excreted into breast milk in small amounts; M/P ratio estimated at 0.2-0.3. Milk concentrations are low (approximately 1-2% of maternal weight-adjusted dose). The American Academy of Pediatrics considers use compatible with breastfeeding, but may cause ergotism in infants (vomiting, diarrhea, seizures) with prolonged use. Short-term use for postpartum hemorrhage is generally acceptable.
Ergotamine is excreted into breast milk with a milk-to-plasma ratio of approximately 0.5-0.9. Potential for ergotism symptoms in infants (vomiting, diarrhea, seizures). It may also reduce milk production due to prolactin inhibition. Contraindicated during breastfeeding per manufacturer guidelines. If exposure occurs, monitor infant for symptoms and consider abrupt cessation.
No dose adjustment required for pregnancy because drug is contraindicated during pregnancy due to uterotonic effects. In postpartum use (which is the approved indication), no pharmacokinetic changes necessitate dose adjustment; normal adult dosing applies (0.2 mg IM/IV for ergometrine, 0.2 mg IM for methylergonovine).
Pregnancy may alter ergotamine pharmacokinetics (increased plasma volume, renal clearance, hepatic metabolism), but no established dose adjustment guidelines. Standard doses may be ineffective or toxic due to variable absorption. Avoid use if possible; if necessary, lowest effective dose for shortest duration, with close monitoring for toxicity.
Administer intramuscularly or intravenously (slow push over 1 minute) for uterine atony; avoid in hypertension, preeclampsia, and sepsis. Store ampules protected from light; discard if discolored. Contraindicated in impaired hepatic or renal function.
Ergomar (ergotamine tartrate sublingual tablets) is a first-line abortive therapy for acute migraine attacks, but its use is limited by vasoconstrictive risks. Avoid in patients with coronary artery disease, hypertension, peripheral vascular disease, or pregnancy. Administer at the first sign of migraine; sublingual route offers rapid absorption. Concomitant use with potent CYP3A4 inhibitors (e.g., macrolides, protease inhibitors) is contraindicated due to risk of ergotism. Limit total dose to 6 mg per attack and 10 mg per week.
This medication may cause nausea, vomiting, or headache.,Report severe abdominal pain, chest pain, or difficulty breathing immediately.,Avoid driving or operating machinery if dizziness occurs.,Do not use during pregnancy except for postpartum hemorrhage.,Inform your doctor if you have high blood pressure, heart disease, or are breastfeeding.
Take one sublingual tablet at the first sign of migraine, placing it under the tongue to dissolve, and do not swallow.,Do not exceed 3 tablets per attack or 5 tablets per week; overuse can lead to serious side effects.,Seek immediate medical attention if you experience symptoms of ergotism like severe coldness, numbness, or pain in hands/feet, muscle cramps, chest pain, or rapid heartbeat.,Avoid grapefruit and grapefruit juice during treatment as it may increase the risk of side effects.,Inform your doctor if you are pregnant, breastfeeding, or have any history of heart disease, high blood pressure, or peripheral artery disease.
"Coadministration of bromocriptine, a dopamine D2 receptor agonist with vasoconstrictive properties, and ergometrine, an ergot alkaloid that acts as a partial agonist at alpha-adrenergic and serotonin receptors, synergistically increases peripheral vasoconstriction. This additive effect can lead to severe hypertension, myocardial ischemia, cerebral vasospasm, and potentially life-threatening ergotism. Patients may present with headache, chest pain, altered mental status, or peripheral ischemia."
"Nylidrin, a beta-adrenergic agonist, and ergometrine, an ergot alkaloid with vasoconstrictive properties, exhibit a synergistic hypertensive effect. By stimulating beta-2 receptors, nylidrin may cause peripheral vasodilation and reflex tachycardia, while ergometrine induces vasoconstriction via alpha-adrenergic and serotonin receptor activation. This opposing mechanism can lead to unopposed vasoconstriction, potentially resulting in severe hypertension, myocardial ischemia, or stroke."
"Simvastatin, a HMG-CoA reductase inhibitor, may increase the serum concentration of ergometrine, an ergot alkaloid used for postpartum hemorrhage, by inhibiting its metabolism via CYP3A4. This can lead to enhanced vasoconstrictive effects of ergometrine, potentially causing severe hypertension, myocardial ischemia, or peripheral vasospasm. Concomitant use poses a risk of ergotism, manifesting as ischemic complications, and should be approached with caution."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about Ergometrine / Methylergonovine vs ERGOMAR, answered by our medical review team.
Ergometrine / Methylergonovine is a Ergot Alkaloid Uterotonic that works by 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.. ERGOMAR is a Ergot Alkaloid Antimigraine that works by Ergotamine acts as a partial agonist at serotonin 5-HT1B and 5-HT1D receptors, causing vasoconstriction of cranial blood vessels. It also inhibits norepinephrine reuptake and has alpha-adrenergic blocking activity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between Ergometrine / Methylergonovine and ERGOMAR depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of Ergometrine / Methylergonovine is: 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.. The standard adult dose of ERGOMAR is: Ergotamine tartrate 1-2 mg sublingually or orally at onset of migraine, then 1-2 mg every 30 minutes as needed, maximum 6 mg per attack and 10 mg per week.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between Ergometrine / Methylergonovine and ERGOMAR in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. Ergometrine / Methylergonovine is classified as Category C. First trimester: Limited human data; animal studies show embryotoxicity and fetotoxicity at high doses due to uterotonic effects, but no structural malformations. Increased risk of. ERGOMAR is classified as Category C. Ergotamine (ERGOMAR) is contraindicated in pregnancy due to its oxytocic properties and potential for uterine hyperstimulation, fetal hypoxia, and congenital anomalies. First trime. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.