Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
METHERGINE vs AKTOB
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
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.
Immunosuppressant; inhibits T-cell activation by binding to cyclophilin and inhibiting calcineurin, thereby blocking IL-2 transcription.
Prevention and treatment of postpartum hemorrhage due to uterine atony,Management of incomplete abortion
Prevention of organ rejection in kidney, liver, and heart transplants,Rheumatoid arthritis,Psoriasis
0.2 mg intramuscularly or intravenously after delivery of placenta and every 2-4 hours as needed, up to a maximum of 5 doses.
Adults: 10 mg orally once daily.
Terminal elimination half-life is approximately 2–3 hours in healthy adults; prolonged in hepatic impairment.
Terminal elimination half-life is 8-12 hours; prolonged in renal impairment (up to 20-30 hours in anuria).
Primarily hepatic via CYP3A4 with significant first-pass metabolism; active metabolite is methylergonovine itself; excreted mainly in bile and urine.
Hepatic via CYP3A4 enzyme system; major metabolites include AM1, AM9, and AM4N.
Primarily hepatic metabolism; less than 1% excreted unchanged in urine. Biliary/fecal excretion accounts for ~80% of metabolites.
Renal: 70-80% unchanged; biliary/fecal: 10-15% as metabolites.
Approximately 93% bound, primarily to albumin and alpha-1-acid glycoprotein.
20-30% primarily to albumin.
0.6 L/kg (range 0.3–0.8 L/kg), indicating moderate distribution into tissues.
0.25-0.4 L/kg; indicates distribution primarily in extracellular fluid.
Oral bioavailability is approximately 10–20% due to extensive first-pass metabolism. Intramuscular administration provides 100% bioavailability.
Intramuscular: approximately 90%; oral: not absorbed (0% due to degradation in GI tract).
No specific dose adjustment recommended; use with caution in renal impairment due to risk of hypertension.
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.
Contraindicated in severe hepatic impairment (Child-Pugh class C). For Child-Pugh class A or B, use with caution and monitor for signs of toxicity.
Child-Pugh A: no adjustment; Child-Pugh B: 5 mg once daily; Child-Pugh C: not recommended.
Not recommended for pediatric use; safety and efficacy in children have not been established.
Not established for children <18 years.
Use with caution in elderly patients due to increased sensitivity to vasoconstrictive effects and higher risk of hypertension and myocardial ischemia.
No specific dose adjustment; monitor for hypotension and renal function.
Not for use during pregnancy (except during delivery) due to risk of uterine tetany and fetal hypoxia. Contraindicated in patients with hypertension, preeclampsia, or eclampsia due to risk of severe hypertension and stroke.
Increased risk of lymphomas and other malignancies, particularly of the skin. Increased susceptibility to infections. Cyclosporine can cause nephrotoxicity and hepatotoxicity.
Risk of severe hypertension, especially in patients with preeclampsia, eclampsia, or hypertension.,Use with caution in patients with sepsis, hepatic or renal impairment, or coronary artery disease.,May cause ergotism with prolonged use or high doses (symptoms: vasospasm, ischemia).,Monitor blood pressure and uterine response during administration.
Nephrotoxicity, hepatotoxicity, hypertension, hyperkalemia, neurotoxicity, increased risk of infections and malignancies, anaphylaxis (IV formulation).
Hypersensitivity to ergot alkaloids,Pregnancy (for antepartum use),Hypertension, preeclampsia, or eclampsia,Peripheral vascular disease,Coronary artery disease,Severe hepatic or renal impairment,Sepsis
Hypersensitivity to cyclosporine or any component of the formulation, abnormal renal function, uncontrolled hypertension, malignancies, concurrent use with PUVA or UVB therapy in psoriasis.
Avoid grapefruit juice as it may increase serum levels of methylergonovine via CYP3A4 inhibition. No specific food restrictions other than avoiding excessive caffeine intake, which may potentiate vasoconstrictive effects.
No significant food interactions. Avoid alcohol while taking this medication.
Methergine (methylergonovine) is contraindicated in pregnancy due to its oxytocic properties and risk of uterine hyperstimulation, fetal distress, and abortion. First trimester: potential teratogenic effects not well studied; avoid use. Second and third trimesters: can cause abruptio placentae, premature labor, and fetal anoxia. It is FDA Pregnancy Category X.
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.
Methylergonovine is excreted into breast milk in small amounts; the milk-to-plasma ratio is approximately 1.0. Adverse effects in nursing infants are rare but may include diarrhea, vomiting, and hypertension. It is generally considered compatible with breastfeeding when used short-term for postpartum hemorrhage. Avoid prolonged use.
Not recommended during breastfeeding. M/P ratio unknown; potential infant exposure via milk.
Not applicable; the drug is contraindicated during pregnancy. No dose adjustments are recommended for use during pregnancy as it should not be used.
No standard dose adjustment; increased clearance in pregnancy may require higher doses; therapeutic drug monitoring advised.
METHERGINE (methylergonovine) is an ergot alkaloid used primarily for postpartum hemorrhage due to uterine atony. Do not use for routine induction of labor or for threatened abortion. Avoid in patients with hypertension, preeclampsia, coronary artery disease, or severe hepatic/renal disease. Monitor blood pressure closely during administration. Administer intramuscularly for rapid effect; onset is 2-5 minutes. Intravenous administration should be reserved for emergencies due to risk of hypertensive crisis. Contraindicated in pregnancy except immediately after delivery. Drug interactions: avoid concurrent use with strong CYP3A4 inhibitors (e.g., ketoconazole, macrolides, protease inhibitors) due to risk of ergotism and vasospasm. As of April 2025, there is no generic form; brand METHERGINE only.
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 is used to prevent or treat excessive bleeding after childbirth by causing contractions of the uterus.,Report immediately if you experience severe headache, chest pain, vision changes, muscle cramps, or numbness/tingling in the arms or legs.,Avoid breastfeeding within 8 hours after the last dose if possible; if breastfeeding is necessary, pump and discard for 8 hours to reduce infant exposure.,Do not use this medication if you have uncontrolled high blood pressure, heart disease, or liver/kidney disease.,Avoid alcohol and grapefruit juice while on this medication as they may affect blood levels.,Take this medication exactly as prescribed; do not take double doses if a dose is missed.
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.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about METHERGINE vs AKTOB, answered by our medical review team.
METHERGINE is a Ergot Alkaloid Uterotonic that works by 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.. 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 METHERGINE 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 METHERGINE is: 0.2 mg intramuscularly or intravenously after delivery of placenta and every 2-4 hours as needed, up to a maximum of 5 doses.. 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 METHERGINE 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. METHERGINE is classified as Category C. Methergine (methylergonovine) is contraindicated in pregnancy due to its oxytocic properties and risk of uterine hyperstimulation, fetal distress, and abortion. First trimester: po. 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.