Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
AMIKACIN SULFATE vs BETHKIS
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
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.
Tobramycin, an aminoglycoside antibiotic, binds to the 30S ribosomal subunit, causing misreading of m RNA and inhibiting protein synthesis, leading to bacterial cell death.
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.
Management of cystic fibrosis patients with Pseudomonas aeruginosa infection
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.
4 IU/kg (1 mg/kg) intramuscularly or subcutaneously once weekly for 4 weeks, then a maintenance dose of 2 IU/kg (0.5 mg/kg) once weekly.
Terminal: 2-3 hours (normal renal function); prolonged to 30-50 hours in anuria; neonates 4-8 hours.
Terminal elimination half-life 2-3 hours in patients with normal renal function; prolonged to 20-40 hours in severe renal impairment (Cr Cl <30 m L/min).
Amikacin is not significantly metabolized; it is excreted unchanged primarily by glomerular filtration. Minimal hepatic metabolism.
Primarily excreted unchanged in urine via glomerular filtration; minimal hepatic metabolism.
Renal: >90% unchanged via glomerular filtration. Biliary/fecal: <1%.
Primarily renal excretion of unchanged drug via glomerular filtration; ~90% of absorbed dose excreted in urine within 24 hours; biliary/fecal elimination <5%.
0-11% (low binding to albumin).
Low protein binding: 10-20%; primarily binds to albumin.
0.25-0.4 L/kg; approximates extracellular fluid volume; increased in edema, decreased in dehydration.
0.2-0.4 L/kg; distributes primarily into extracellular fluid; limited intracellular penetration.
IM: nearly 100% (rapid and complete).
Inhalation: ~50-60% of nominal dose reaches systemic circulation; oral: negligible (<1% due to poor gastrointestinal absorption).
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.
No dose adjustment required for renal impairment. Not removed by hemodialysis.
No dose adjustment required for hepatic impairment; monitor drug levels if severe dysfunction.
No dose adjustment recommended for mild to moderate hepatic impairment (Child-Pugh A or B). Use with caution in severe hepatic impairment (Child-Pugh C) due to lack of data.
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.
Weight-based dosing: 4 IU/kg (1 mg/kg) intramuscularly or subcutaneously once weekly for 4 weeks, then 2 IU/kg (0.5 mg/kg) once weekly. Safety and efficacy in children <18 years not established.
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.
No specific dose adjustments recommended. Use with caution due to potential age-related decline in renal and hepatic function. Monitor for adverse effects.
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 nephrotoxicity and ototoxicity; monitor renal function and hearing during therapy.
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.
Nephrotoxicity, ototoxicity (vestibular and auditory), neuromuscular blockade, hypersensitivity, superinfection.
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).
Hypersensitivity to tobramycin or other aminoglycosides.
No significant food interactions. Avoid alcohol as it may increase side effects like dizziness.
No specific food interactions. Maintain adequate hydration; avoid excessive salt intake if concurrent diuretics are used.
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.
Insufficient human data; animal studies show no teratogenic effects at doses up to 4 times the human dose. Risk cannot be ruled out; use only if clearly needed.
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.
Unknown if excreted in human breast milk; M/P ratio not available. Caution advised due to risk of infant bowel flora alteration and potential for tobramycin-related ototoxicity or nephropathy.
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.
No specific dose adjustments recommended; pharmacokinetics may be altered due to increased volume of distribution and GFR; monitor serum levels and adjust to maintain therapeutic trough <2 mcg/m L.
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.
Administer via inhalation only using a suitable nebulizer; do not mix with other drugs in the nebulizer. Monitor for bronchospasm; consider pretreatment with a bronchodilator in patients with reactive airway disease. Assess renal function before and during therapy due to potential nephrotoxicity. Obtain audiometric testing at baseline and periodically due to ototoxicity risk. Avoid concurrent use of loop diuretics or other nephrotoxic drugs. Trough serum tobramycin concentrations should be measured after 2–3 doses when systemic absorption is suspected.
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.
Use Bethkis exactly as prescribed; do not skip doses or double up.,Do not swallow or inject Bethkis; it is for inhalation only.,Use a nebulizer with a mouthpiece; do not use a face mask unless necessary.,Store vials in the refrigerator; protect from light.,Clean and disinfect the nebulizer after each use.,Report hearing loss, ringing in the ears, dizziness, or changes in urine output immediately.,Avoid other inhaled medications within 30 minutes of Bethkis unless directed.,Inform your healthcare provider of all other medications, especially diuretics and other antibiotics.
"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."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about AMIKACIN SULFATE vs BETHKIS, answered by our medical review team.
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.. BETHKIS is a Aminoglycoside Antibiotic that works by Tobramycin, an aminoglycoside antibiotic, binds to the 30S ribosomal subunit, causing misreading of m RNA and inhibiting protein synthesis, leading to bacterial cell death.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between AMIKACIN SULFATE and BETHKIS depend on the specific clinical indication. These are both Aminoglycoside Antibiotic agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
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.. The standard adult dose of BETHKIS is: 4 IU/kg (1 mg/kg) intramuscularly or subcutaneously once weekly for 4 weeks, then a maintenance dose of 2 IU/kg (0.5 mg/kg) once weekly.. 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 AMIKACIN SULFATE and BETHKIS 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. 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 . BETHKIS is classified as Category C. Insufficient human data; animal studies show no teratogenic effects at doses up to 4 times the human dose. Risk cannot be ruled out; use only if clearly needed.. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.