Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
Ergometrine / Methylergonovine vs AKTOB
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.
Immunosuppressant; inhibits T-cell activation by binding to cyclophilin and inhibiting calcineurin, thereby blocking IL-2 transcription.
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)
Prevention of organ rejection in kidney, liver, and heart transplants,Rheumatoid arthritis,Psoriasis
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.
Adults: 10 mg orally once daily.
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 8-12 hours; prolonged in renal impairment (up to 20-30 hours in anuria).
Primarily hepatic via CYP3A4; also undergoes first-pass metabolism. Metabolites are excreted in urine and bile.
Hepatic via CYP3A4 enzyme system; major metabolites include AM1, AM9, and AM4N.
Renal (20% unchanged), biliary/fecal (35% as metabolites and parent compound)
Renal: 70-80% unchanged; biliary/fecal: 10-15% as metabolites.
85-90% (primarily to albumin and α1-acid glycoprotein)
20-30% primarily to albumin.
0.4-0.6 L/kg; clinical meaning: moderate tissue distribution, consistent with limited extravascular binding
0.25-0.4 L/kg; indicates distribution primarily in extracellular fluid.
Oral: 20-40% (due to extensive first-pass metabolism); IM: ~80%
Intramuscular: approximately 90%; oral: not absorbed (0% due to degradation in GI tract).
No specific guidelines; use with caution in severe renal impairment (GFR <30 m L/min) due to risk of accumulation and hypertensive effects.
GFR 30-89 m L/min: no adjustment; GFR 15-29 m L/min: 5 mg once daily; GFR <15 m L/min or dialysis: 2.5 mg once daily.
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: no adjustment; Child-Pugh B: 5 mg once daily; Child-Pugh C: not recommended.
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 established for children <18 years.
Use lowest effective dose due to increased sensitivity and higher risk of hypertension and coronary vasospasm; consider 0.1 mg initially and titrate cautiously.
No specific dose adjustment; monitor for hypotension and renal function.
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.
Increased risk of lymphomas and other malignancies, particularly of the skin. Increased susceptibility to infections. Cyclosporine can cause nephrotoxicity and hepatotoxicity.
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.
Nephrotoxicity, hepatotoxicity, hypertension, hyperkalemia, neurotoxicity, increased risk of infections and malignancies, anaphylaxis (IV formulation).
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 cyclosporine or any component of the formulation, abnormal renal function, uncontrolled hypertension, malignancies, concurrent use with PUVA or UVB therapy in psoriasis.
No known food interactions.
No significant food interactions. Avoid alcohol while taking this medication.
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.
First trimester: Limited human data; animal studies show adverse effects at high doses. Avoid unless benefit outweighs risk. Second/third trimester: No documented teratogenicity; monitor for fetal growth restriction and oligohydramnios.
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.
Not recommended during breastfeeding. M/P ratio unknown; potential infant exposure via milk.
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).
No standard dose adjustment; increased clearance in pregnancy may require higher doses; therapeutic drug monitoring advised.
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.
AKTOB is a beta-lactam antibiotic; monitor for hypersensitivity reactions, especially in patients with penicillin allergy. Adjust dose in renal impairment (Cr Cl <30 m L/min). Administer by slow IV infusion over 3-5 minutes or as directed. Observe for signs of Clostridioides difficile infection.
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.
Complete the full course of therapy even if symptoms improve.,Report any signs of allergic reaction such as rash, itching, or difficulty breathing immediately.,Inform your doctor if you have kidney problems or are on dialysis.,This medication may cause diarrhea; do not treat with anti-diarrheal medications without consulting your doctor.,Store at room temperature away from moisture and heat.
"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 AKTOB, 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.. AKTOB is a Aminoglycoside Antibiotic (Ophthalmic) that works by Immunosuppressant; inhibits T-cell activation by binding to cyclophilin and inhibiting calcineurin, thereby blocking IL-2 transcription.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between Ergometrine / Methylergonovine and AKTOB 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 AKTOB is: Adults: 10 mg orally once daily.. 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 AKTOB 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. AKTOB is classified as Category C. First trimester: Limited human data; animal studies show adverse effects at high doses. Avoid unless benefit outweighs risk. Second/third trimester: No documented teratogenicity; m. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.