Aminoglycoside類抗生素

Serious infections (eg, sepsis, meningitis, urinary tract infections, respiratory tract infections, peritonitis, bone infections, skin and soft tissue infections):
caused by susceptible strains of the following microorganisms: Pseudomonas aeruginosa, Proteus species (indole-positive and indole-negative), Escherichia coli, Klebsiella species, Enterobacter species, Serratia species, Citrobacter species, and Staphylococcus species (coagulase-positive and coagulase-negative)
Infective endocarditis:
caused by enterococci, in combination with other antibiotics.

Aminoglycoside antibiotic
Gentamicin sulfate is an aminoglycoside antibiotic which acts by inhibiting microbial protein synthesis in susceptible pathogens.

Absorption
Tmax, IM: 30 to 60 minutes
Distribution
1. Protein binding: 0% to 30%
2. Vd, adult：0.29 to 0.37 L/kg
3. Vd, pediatrics：0.34 to 0.46 L/kg
Metabolism
minimal
Excretion
Renal excretion: 65% to 100%
Elimination Half Life
Adults：2 hours; Pediatrics：3.05 to 3.9 hours

Hypersensitivity to gentamicin or other aminoglycosides; cross-sensitivity may occur.

D [FDA] D [AUS]

Infant risk is minimal. [MDX]

Neurologic: Neuromuscular blockade finding.
Otic: Ototoxicity.
Renal: Nephrotoxicity.
Respiratory: Respiratory tract paralysis, Concomitant anesthesia, muscle relaxants.

Usual dosage:

Gram-negative infections:
1. Conventional dosing: (IV, IM) 3-5 mg/kg/day in divided doses every 8 hours.
2. High-dose extended-interval dosing: (IV) 5 to 7 mg/kg once daily; not recommended in patients with ascites, burns covering >20% of the total body surface area, end-stage renal disease (eg, requiring hemodialysis), or pregnancy (except for intrapartum therapy for intra-amniotic infection)

Synergy dosing for non-CNS gram-positive infections: (IV, IM) 3 mg/kg/day in 1 to 3 divided doses in combination with a gram-positive active agent
Indication-specific dosing:

Bloodstream infection: (IV) 5 to 7 mg/kg once daily in combination with a second gram-negative active agent

Endocarditis, Enterococcus spp. infection: (IV, IM) 1 mg/kg every 8 hours as part of an appropriate combination regimen.

Meningitis:
1. Enterococcus spp. infection: (IV) 5 mg/kg/day in 1 or 3 divided doses
2. Listeria monocytogenes infection: (IV) 5 mg/kg/day in 3 divided doses in combination with ampicillin or penicillin.

Sepsis or septic shock, adjunctive empiric gram-negative coverage (eg, in the setting of intra-abdominal infection, pneumonia, gram-negative bacteremia, or severe burn): (IV) 5 to 7 mg/kg once daily in combination with a second gram-negative agent

Urinary tract infection, alternative: (IV, IM) 5 mg/kg once daily.

Children, 1 year or older: 6 to 7.5 mg/kg/day IV/IM in equally divided doses every 8 hours for 7 to 10 days (FDA)
Infants and neonates, 1 year or younger: 7.5 mg/kg/day IV/IM in equally divided doses every 8 hours for 7 to 10 days (FDA)

Conventional dosing:
1. GFR >50 mL/minute: No dosage adjustment necessary
2. GFR 10-50 mL/minute: Administer every 12 to 48 hours
3. GFR <10 mL/minute: Administer every 48 to 72 hours
Once daily extended-interval dosing:
1. CrCl >60 mL/minute: Administer every 24 hours
2. CrCl 40-59 mL/minute: Administer every 36 hours
3. CrCl 20-39 mL/minute: Administer every 48 hours
4. CrCl <20 mL/minute: Monitor serum levels and redose when gentamicin level is less than 1 mcg/mL or use conventional dosing.
Note: In patients with sepsis/septic shock and severe renal impairment, the SSC guidelines do not recommend use of once-daily dosing. Patients with mild renal impairment should still receive once-daily dosing with an extended interval (ie, up to 3 days)
Intermittent hemodialysis (IHD) (administer after hemodialysis on dialysis days):
Loading dose of 2 to 3 mg/kg loading dose followed by:
1. Mild UTI or synergy: 1 mg/kg/dose every 48 to 72 hours; consider redosing for pre-HD or post-HD concentrations <1 mg/L
2. Moderate-to-severe UTI: 1 to 1.5 mg/kg/dose every 48 to 72 hours; consider redosing for pre-HD concentrations <1.5 to 2 mg/L or post-HD concentrations <1 mg/L
3. Systemic gram-negative rod infection: 1.5 to 2 mg/kg/dose every 48 to 72 hours; consider redosing for pre-HD concentrations <3 to 5 mg/L or post-HD concentrations <2 mg/L
Continuous renal replacement therapy (CRRT):
Loading dose of 2 to 3 mg/kg loading dose followed by:
1. Mild UTI or synergy: 1 mg/kg every 24 to 36 hours (redose when concentration <1 mg/L)
2. Moderate to severe UTI: 1 to 1.5 mg/kg every 24 to 36 hours (redose when concentration <1.5 to 2 mg/L)
3. Systemic gram-negative infection: 1.5 to 2.5 mg/kg every 24 to 48 hours (generally accepted to redose when concentration <2 mg/L; one reference suggests redosing when <3 mg/L

No dosage reductions are required in liver disease.

Store at controlled room temperature, between 20 and 25 degrees C.