Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
METHERGINE vs AMIKACIN SULFATE
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.
Aminoglycoside antibiotic that irreversibly binds to the 30S ribosomal subunit, causing misreading of m RNA and inhibiting protein synthesis. Also disrupts bacterial cell membrane integrity.
Prevention and treatment of postpartum hemorrhage due to uterine atony,Management of incomplete abortion
FDA-approved: Treatment of serious gram-negative bacterial infections (e.g., Pseudomonas aeruginosa, Escherichia coli, Klebsiella, Enterobacter, Serratia, Proteus) when other antibiotics are ineffective or contraindicated.,Off-label: Used in combination for enterococcal endocarditis, mycobacterial infections (e.g., tuberculosis), and severe neonatal sepsis.
0.2 mg intramuscularly or intravenously after delivery of placenta and every 2-4 hours as needed, up to a maximum of 5 doses.
15 mg/kg/day IV or IM divided every 8-12 hours; typical adult dose 500 mg IV/IM every 12 hours or 7.5 mg/kg every 12 hours.
Terminal elimination half-life is approximately 2–3 hours in healthy adults; prolonged in hepatic impairment.
Terminal: 2-3 hours (normal renal function); prolonged to 30-50 hours in anuria; neonates 4-8 hours.
Primarily hepatic via CYP3A4 with significant first-pass metabolism; active metabolite is methylergonovine itself; excreted mainly in bile and urine.
Amikacin is not significantly metabolized; it is excreted unchanged primarily by glomerular filtration. Minimal hepatic metabolism.
Primarily hepatic metabolism; less than 1% excreted unchanged in urine. Biliary/fecal excretion accounts for ~80% of metabolites.
Renal: >90% unchanged via glomerular filtration. Biliary/fecal: <1%.
Approximately 93% bound, primarily to albumin and alpha-1-acid glycoprotein.
0-11% (low binding to albumin).
0.6 L/kg (range 0.3–0.8 L/kg), indicating moderate distribution into tissues.
0.25-0.4 L/kg; approximates extracellular fluid volume; increased in edema, decreased in dehydration.
Oral bioavailability is approximately 10–20% due to extensive first-pass metabolism. Intramuscular administration provides 100% bioavailability.
IM: nearly 100% (rapid and complete).
No specific dose adjustment recommended; use with caution in renal impairment due to risk of hypertension.
Cr Cl 20-50 m L/min: 7.5 mg/kg every 24 hours; Cr Cl 10-20 m L/min: 7.5 mg/kg every 48 hours; Cr Cl <10 m L/min: 7.5 mg/kg every 72-96 hours; hemodialysis: 7.5 mg/kg post-dialysis with monitoring.
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.
No dose adjustment required for hepatic impairment; monitor drug levels if severe dysfunction.
Not recommended for pediatric use; safety and efficacy in children have not been established.
Neonates <7 days: 15-20 mg/kg IV every 24-48 hours; neonates 7-28 days: 15 mg/kg every 24 hours; infants/children: 15-22.5 mg/kg/day divided every 8-12 hours; maximum 1.5 g/day.
Use with caution in elderly patients due to increased sensitivity to vasoconstrictive effects and higher risk of hypertension and myocardial ischemia.
Reduce initial dose based on renal function; usual dose 7.5 mg/kg every 24-48 hours with close monitoring of serum creatinine and drug levels due to age-related decreased GFR.
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.
WARNING: Amikacin can cause neurotoxicity, ototoxicity, and nephrotoxicity. The risk of nephrotoxicity is greater in patients with impaired renal function and those receiving high doses or prolonged therapy. Ototoxicity may be irreversible and can occur even after drug discontinuation. Monitor renal function and drug levels closely.
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: Risk increased with advanced age, pre-existing renal impairment, concomitant use of other nephrotoxic drugs (e.g., amphotericin B, cyclosporine, NSAIDs).,Ototoxicity: Can cause irreversible bilateral hearing loss, tinnitus, and vestibular damage. Monitor audiometry in patients with risk factors.,Neuromuscular blockade: May exacerbate weakness in patients with neuromuscular disorders (e.g., myasthenia gravis, Parkinsonism). Use with caution during anesthesia or with neuromuscular blocking agents.,Hypersensitivity reactions: Including rash, drug fever, and anaphylaxis.,Superinfection: Prolonged use may lead to overgrowth of nonsusceptible organisms.,Pregnancy: Risk of fetal harm (ototoxicity) if administered during pregnancy.
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 amikacin, other aminoglycosides, or any component of the formulation.,Preexisting severe renal impairment (unless life-threatening infection and no alternative).,Concurrent use of other nephrotoxic or ototoxic drugs (relative contraindication).,Myasthenia gravis (caution; neuromuscular blocking effect).
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 as it may increase side effects like dizziness.
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.
Aminoglycosides including amikacin have been associated with fetal ototoxicity and nephrotoxicity when administered during pregnancy. There is a potential for eighth cranial nerve damage and renal impairment in the fetus, particularly during the second and third trimesters. Animal studies have shown evidence of harm, but controlled human studies are lacking. Use only if clearly needed and if safer alternatives are unavailable.
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.
Amikacin is excreted into human milk in low concentrations. The milk-to-plasma ratio is approximately 0.1–0.2. Due to low oral bioavailability from the gastrointestinal tract, systemic effects in the breastfed infant are unlikely. However, caution is advised due to the potential for altered infant gut flora and direct mucosal irritation. Use only if benefits outweigh risks.
Not applicable; the drug is contraindicated during pregnancy. No dose adjustments are recommended for use during pregnancy as it should not be used.
Pregnancy does not typically require dosing adjustments for amikacin. However, due to increased glomerular filtration rate during pregnancy, levels may be lower; monitor drug concentrations and adjust doses to achieve therapeutic range. Standard dosing based on ideal body weight and renal function should be followed.
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.
Monitor peak (15-30 mcg/m L) and trough (<5 mcg/m L) levels to avoid nephrotoxicity and ototoxicity. Adjust dose in renal impairment using Cr Cl. Synergy with beta-lactams for Gram-negative infections. Avoid concurrent loop diuretics.
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.
Take exactly as prescribed; do not skip doses or stop early.,Report any hearing loss, tinnitus, dizziness, or vertigo immediately.,Drink plenty of fluids to maintain hydration, unless contraindicated.,Avoid taking other medications without consulting your doctor, especially water pills or other antibiotics.
No interactions on record
"Amikacin, an aminoglycoside antibiotic, may competitively inhibit the renal tubular secretion and potentially reduce the clearance of masoprocol, a dicarboxylic acid derivative used as a chemotherapeutic agent. This interaction could lead to increased systemic exposure to masoprocol, elevating the risk of dose-dependent toxicities such as severe enteritis, myelosuppression, and hepatotoxicity. Given the narrow therapeutic index of masoprocol, even modest elevations in serum levels may result in clinically significant adverse outcomes."
"Amikacin, an aminoglycoside antibiotic, may competitively inhibit the tubular secretion of mycophenolic acid (MPA) in the renal proximal tubules, leading to reduced renal clearance of MPA. This interaction can result in elevated serum levels of MPA, increasing the risk of dose-related toxicities such as bone marrow suppression (leukopenia, thrombocytopenia), gastrointestinal disturbances, and increased susceptibility to infections. Patients receiving this combination should be closely monitored for signs of MPA toxicity, especially those with pre-existing renal impairment."
"Coadministration of Metocurine, a nondepolarizing neuromuscular blocking agent, with Amikacin, an aminoglycoside antibiotic, may result in enhanced and prolonged neuromuscular blockade. Aminoglycosides can impair acetylcholine release from presynaptic nerve terminals and reduce postsynaptic sensitivity, synergistically augmenting the effects of nondepolarizing agents. This interaction can lead to excessive muscle relaxation, including respiratory muscle paralysis, increasing the risk of apnea and postoperative respiratory depression."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about METHERGINE vs AMIKACIN SULFATE, 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.. AMIKACIN SULFATE is a Aminoglycoside Antibiotic that works by Aminoglycoside antibiotic that irreversibly binds to the 30S ribosomal subunit, causing misreading of m RNA and inhibiting protein synthesis. Also disrupts bacterial cell membrane integrity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between METHERGINE and AMIKACIN SULFATE 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 AMIKACIN SULFATE is: 15 mg/kg/day IV or IM divided every 8-12 hours; typical adult dose 500 mg IV/IM every 12 hours or 7.5 mg/kg every 12 hours.. 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 AMIKACIN SULFATE 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. AMIKACIN SULFATE is classified as Category D/X. Aminoglycosides including amikacin have been associated with fetal ototoxicity and nephrotoxicity when administered during pregnancy. There is a potential for eighth cranial nerve . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.