Gentamicin In Nacl (Iso-Osm) (gentamicin sulfate in sodium chloride, iso-osmotic)

Dosage of gentamicin sulfate is expressed in terms of gentamicin. IM and IV dosage is identical.

Like other aminoglycosides, dosage of gentamicin should be individualized taking into consideration the patient's pretreatment body weight, renal status, severity of the infection, and susceptibility of the causative organism. The manufacturers state that dosage in obese patients should be based on the patient's estimated lean body weight. Many clinicians recommend that gentamicin dosage be determined using appropriate pharmacokinetic methods for calculating dosage requirements and patient-specific pharmacokinetic parameters (e.g., elimination rate constant, volume of distribution) derived from serum concentration-time data.

Whenever possible, especially in patients with life-threatening infections, suspected toxicity or nonresponse to treatment, decreased or varying renal function, and/or when increased aminoglycoside clearance (e.g., patients with cystic fibrosis, burns) or prolonged therapy is likely, peak and trough serum concentrations of gentamicin should be determined periodically and dosage should be adjusted to maintain desired serum concentrations. (See Dosage and Administration: Dosage, in the Aminoglycosides General Statement 8:12.02.) A causal relationship between maintenance of certain peak or trough serum concentrations or other pharmacodynamic endpoints and clinical response or toxicity has not been established to date for gentamicin dosing regimens. However, for gentamicin administered in conventional dosage regimens (i.e., multiple daily doses), peak serum concentrations of 4-10 mcg/mL and trough concentrations that do not exceed 1-2 mcg/mL have been suggested. An increased risk of toxicity may be associated with peak serum gentamicin concentrations greater than 10-12 mcg/mL and/or trough concentrations greater than 2 mcg/mL. The manufacturers state that prolonged peak serum concentrations greater than 12 mcg/mL and trough concentrations greater than 2 mcg/mL should be avoided.

Parenteral aminoglycosides historically have been administered in dosage regimens that include multiple daily doses, and current prescribing information for IM or IV gentamicin only includes dosage regimens that involve multiple daily doses (usually 3 or 4 doses daily). However, there is evidence that once-daily+ (single-daily) aminoglycoside dosage regimens are at least as effective as, may provide superior pharmacokinetics, and may be less toxic than conventional dosage regimens employing multiple daily doses of the drugs. Although once-daily gentamicin regimens are recommended for some indications, once-daily gentamicin regimens should not be used in all patients and should not be used for the treatment of enterococcal or staphylococcal endocarditis+. Additional controlled studies in children, patients with renal dysfunction, and other appropriate patient groups are needed to fully define the optimal use of once-daily aminoglycoside dosing regimens. In addition, the most appropriate methods for optimizing dosage selection for once-daily regimens and monitoring serum aminoglycoside concentrations in patients receiving such regimens have not been clearly established. (See Dosage and Administration: Dosage, in the Aminoglycosides General Statement 8:12.02.)

The usual duration of gentamicin treatment is 7-10 days. In difficult and complicated infections, a longer course of treatment may be necessary. However, toxicity is more likely to occur if treatment is continued for longer than 10 days and renal, auditory, and vestibular functions should be monitored closely.

In patients with impaired renal function, doses and/or frequency of administration must be modified in response to serum concentrations of the drug and the degree of renal impairment. There are various methods to determine dosage and a wide variation in dosage recommendations for these patients. However, even when one of these methods is used, peak and trough serum concentrations of the drug should be monitored, especially in patients with changing renal function.

The manufacturers recommend that adults with renal impairment receive an initial dose of 1-1.7 mg/kg. For subsequent therapy, the manufacturers state that 1 mg/kg doses can be given at intervals (in hours) calculated by multiplying the patient's steady-state serum creatinine (in mg/dL) by 8. Alternatively, many clinicians recommend the dosing method of Sarubbi and Hull, which is based on corrected creatinine clearance. (See Dosage and Administration: Dosage in Renal Impairment, in the Aminoglycosides General Statement 8:12.02.) These dosage calculation methods should not be used in patients undergoing hemodialysis or peritoneal dialysis.

In adults with renal failure undergoing hemodialysis, the manufacturers recommend supplemental doses of 1-1.7 mg/kg at the end of each dialysis period in adults and supplemental doses of 2-2.5 mg/kg at the end of each dialysis period in children. Some clinicians suggest supplemental doses of 50-75% of the initial loading dose at the end of each dialysis period. Serum gentamicin concentrations should be monitored in dialysis patients and dosage adjusted as needed to maintain desired serum concentrations.

Gentamicin sulfate is administered by IM injection or IV infusion. IV administration may be preferred in patients with septicemia, shock, congestive heart failure, hematologic disorders, severe burns, or reduced muscle mass.

Gentamicin sulfate has been administered intrathecally+ or intraventricularly+ as an adjunct to IM or IV administration of the drug for the treatment of meningitis and other CNS infections.

Patients should be well hydrated prior to and during gentamicin therapy since dehydration increases the risk of toxicity.

Renal function should be assessed prior to and monitored during gentamicin therapy. Patients should be under close clinical observation because of the risk of ototoxicity and nephrotoxicity. (See Cautions in the Aminoglycosides General Statement 8:12.02.)

Prior to administration, gentamicin solutions should be inspected visually for particulate matter or discoloration.

No dosing information is available for this tab.

No dosing information is available for this tab.

There is no enhanced messaging for this drug.

There are no contraindication interactions for this drug.

There are no severe interactions for this drug.

There are no moderate interactions for this drug.

There is no enhanced messaging for this drug.

There are no contraindication contraindications for this drug.

There are no severe contraindications for this drug.

There are no moderate contraindications for this drug.

There is no enhanced messaging for this drug.

There are no severe adverse reactions for this drug.

There are no less severe adverse reactions for this drug.

No enhanced messaging available.

No enhanced messaging available.

No enhanced messaging available.

No enhanced messaging available.

No enhanced messaging available.