Gentamicin Injection, USP

Rx only

To reduce the development of drug-resistant bacteria and maintain the effectiveness of Gentamicin Injection, USP and other antibacterial drugs, Gentamicin Injection, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

Patients treated with aminoglycosides should be under close clinical observation because of the potential toxicity associated with their use.

As with other aminoglycosides, gentamicin injection is potentially nephrotoxic. The risk of nephrotoxicity is greater in patients with impaired renal function and in those who receive high dosage of prolonged therapy.

Neurotoxicity manifested by ototoxicity, both vestibular and auditory, can occur in patients treated with gentamicin, primarily in those with pre- existing renal damage and in patients with normal renal function treated with higher doses and/or for longer periods than recommended.

Aminoglycoside-induced ototoxicity is usually irreversible. Other manifestations of neurotoxicity may include numbness, skin tingling, muscle twitching and convulsions.

Renal and eighth cranial nerve function should be closely monitored, especially in patients with known or suspected reduced renal function at onset of therapy and also in those whose renal function is initially normal but who develop signs of renal dysfunction during therapy. Urine should be examined for decreased specific gravity, increased excretion of protein and the presence of cells or casts. Blood urea nitrogen (BUN), serum creatinine or creatinine clearance should be determined periodically. When feasible, it is recommended that serial audiograms be obtained in patients old enough to be tested, particularly high-risk patients. Evidence of ototoxicity (dizziness, vertigo, tinnitus, roaring in the ears or hearing loss) or nephrotoxicity requires dosage adjustment or discontinuance of the drug. As with the other aminoglycosides, on rare occasions changes in renal and eighth cranial nerve function may not become manifest until soon after completion of therapy.

Serum concentrations of aminoglycosides should be monitored when feasible to assure adequate levels and to avoid potentially toxic levels. When monitoring gentamicin peak concentrations, dosage should be adjusted so that prolonged levels above 12 mcg/mL are avoided. When monitoring gentamicin trough concentrations, dosage should be adjusted so that levels above 2 mcg/mL are avoided. Excessive peak and/or trough serum concentrations of aminoglycosides may increase the risk of renal and eighth cranial nerve toxicity.

In the event of overdosage or toxic reactions, hemodialysis may aid in the removal of gentamicin from the blood, especially if renal function is, or becomes, compromised. The rate of removal of gentamicin is considerably lower by peritoneal dialysis than it is by hemodialysis.

In the newborn infant, exchange transfusions may also be considered.

Concurrent and/or sequential systemic or topical use of other potentially neurotoxic and/or nephrotoxic drugs, such as cisplatin, cephaloridine, kanamycin, amikacin, neomycin, polymyxin B, colistin, paromomycin, streptomycin, tobramycin, vancomycin and viomycin, should be avoided. Other factors which may increase patient risk of toxicity are advanced age and dehydration.

The concurrent use of gentamicin with potent diuretics, such as ethacrynic acid or furosemide, should be avoided, since certain diuretics by themselves may cause ototoxicity. In addition, when administered intravenously, diuretics may enhance aminoglycoside toxicity by altering the antibiotic concentration in serum and tissue.

Aminoglycosides can cause fetal harm when administered to a pregnant woman (see WARNINGS section).

Gentamicin sulfate, a water-soluble antibiotic of the aminoglycoside group, is derived by the growth of Micromonospora purpurea, an actinomycete. It has the following structural formula.

Structural Formula

Gentamicin injection is a sterile, nonpyrogenic aqueous solution for parenteral administration.

Each mL contains: Gentamicin sulfate equivalent to 40 mg gentamicin, methylparaben 1.8 mg and propylparaben 0.2 mg as preservatives, sodium metabisulfite 3.2 mg and edetate disodium 0.1 mg, Water for Injection q.s. Sodium hydroxide and/or sulfuric acid may have been added for pH adjustment.

After intramuscular (IM) administration of gentamicin sulfate, peak serum concentrations usually occur between 30 and 60 minutes and serum levels are measurable for six to eight hours. When gentamicin is administered by intravenous (IV) infusion over a two-hour period, the serum concentrations are similar to those obtained by IM administration.

In patients with normal renal function, peak serum concentrations of gentamicin (mcg/mL) are usually up to four times the single IM dose (mg/kg); for example, a 1 mg/kg injection in adults may be expected to result in a peak serum concentration up to 4 mcg/mL; a 1.5 mg/kg dose may produce levels up to 6 mcg/mL. While some variation is to be expected due to a number of variables such as age, body temperature, surface area and physiologic differences, the individual patient given the same dose tends to have similar levels in repeated determinations. Gentamicin administered at 1 mg/kg every eight hours for the usual 7 to 10 day treatment period to patients with normal renal function does not accumulate in the serum.

Gentamicin, like all aminoglycosides, may accumulate in the serum and tissues of patients treated with higher doses and/or for prolonged periods, particularly in the presence of impaired renal function. In adult patients, treatment with gentamicin dosages of 4 mg/kg/day or higher for 7 to 10 days may result in a slight, progressive rise in both peak and trough concentrations. In patients with impaired renal function, gentamicin is cleared from the body more slowly than in patients with normal renal function. The more severe the impairment, the slower the clearance. (Dosage must be adjusted.)

Since gentamicin is distributed in extra-cellular fluid, peak serum concentrations may be lower than usual in adult patients who have a large volume of this fluid. Serum concentrations of gentamicin in febrile patients may be lower than those in afebrile patients given the same dose. When body temperature returns to normal, serum concentrations of the drug may rise. Febrile and anemic states may be associated with a shorter than usual serum half-life. (Dosage adjustment is usually not necessary.) In severely burned patients, the half-life may be significantly decreased and resulting serum concentrations may be lower than anticipated from the mg/kg dose.

Protein binding studies have indicated that the degree of gentamicin binding is low; depending upon the methods used for testing, this may be between 0 and 30%.

After initial administration to patients with normal renal function, generally 70% or more of the gentamicin dose is recoverable in the urine in 24 hours; concentrations in urine above 100 mcg/mL may be achieved. Little, if any, metabolic transformation occurs; the drug is excreted principally by glomerular filtration. After several days of treatment, the amount of gentamicin excreted in the urine approaches the daily dose administered. As with other aminoglycosides, a small amount of the gentamicin dose may be retained in the tissues, especially in the kidneys. Minute quantities of aminoglycosides have been detected in the urine weeks after drug administration was discontinued. Renal clearance of gentamicin is similar to that of endogenous creatinine.

In patients with marked impairment of renal function, there is a decrease in the concentration of aminoglycosides in urine and in their penetration into defective renal parenchyma. This decreased drug excretion, together with the potential nephrotoxicity of aminoglycosides, should be considered when treating such patients who have urinary tract infections.

Probenecid does not affect renal tubular transport of gentamicin.

The endogenous creatinine clearance rate and the serum creatinine level have a high correlation with the half-life of gentamicin in serum. Results of these tests may serve as guides for adjusting dosage in patients with renal impairment (see DOSAGE AND ADMINISTRATION).

Following parenteral administration, gentamicin can be detected in serum, lymph, tissues, sputum and in pleural, synovial and peritoneal fluids. Concentrations in renal cortex sometimes may be eight times higher than the usual serum levels. Concentrations in bile, in general, have been low and have suggested minimal biliary excretion. Gentamicin crosses the peritoneal as well as the placental membranes. Since aminoglycosides diffuse poorly into the subarachnoid space after parenteral administration, concentrations of gentamicin in cerebrospinal fluid are often low and dependent upon dose, rate of penetration and degree of meningeal inflammation. There is minimal penetration of gentamicin into ocular tissues following IM or IV administration.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of Gentamicin Injection, USP and other antibacterial drugs, Gentamicin Injection, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

Gentamicin Injection, USP is indicated in the treatment of serious infections caused by susceptible strains of the following microorganisms: Pseudomonas aeruginosa, Proteus species (indole-positive and indole-negative), Escherichia coli, Klebsiella-Enterobacter-Serratia species, Citrobacter species and Staphylococcus species (coagulase-positive and coagulase-negative).

Clinical studies have shown gentamicin injection to be effective in bacterial neonatal sepsis; bacterial septicemia and serious bacterial infections of the central nervous system (meningitis), urinary tract, respiratory tract, gastrointestinal tract (including peritonitis), skin, bone and soft tissue (including burns). Aminoglycosides, including gentamicin, are not indicated in uncomplicated initial episodes of urinary tract infections unless the causative organisms are susceptible to these antibiotics and are not susceptible to antibiotics having less potential for toxicity.

Specimens for bacterial culture should be obtained to isolate and identify causative organisms and to determine their susceptibility to gentamicin.

Gentamicin injection may be considered as initial therapy in suspected or confirmed gram-negative infections, and therapy may be instituted before obtaining results of susceptibility testing. The decision to continue therapy with this drug should be based on the results of susceptibility tests, the severity of the infection and the important additional concepts contained in the BOXED WARNINGS. If the causative organisms are resistant to gentamicin, other appropriate therapy should be instituted.

In serious infections when the causative organisms are unknown, gentamicin injection may be administered as initial therapy in conjunction with a penicillin-type or cephalosporin-type drug before obtaining results of susceptibility testing. If anaerobic organisms are suspected as etiologic agents,

consideration should be given to using other suitable antimicrobial therapy in conjunction with gentamicin. Following identification of the organism and its susceptibility, appropriate antibiotic therapy should then be continued.

Gentamicin injection has been used effectively in combination with carbenicillin for the treatment of life-threatening infections caused by Pseudomonas aeruginosa. It has also been found effective when used in conjunction with a penicillin-type drug for treatment of endocarditis caused by group D streptococci.

Gentamicin injection has also been shown to be effective in the treatment of serious staphylococcal infections. While not the antibiotic of first choice, gentamicin injection may be considered when penicillins or other less potentially toxic drugs are contraindicated and bacterial susceptibility tests and clinical judgment indicate its use. It may also be considered in mixed infections caused by susceptible strains of staphylococci and gram-negative organisms.

In the neonate with suspected bacterial sepsis or staphylococcal pneumonia, a penicillin-type drug is also usually indicated as concomitant therapy with gentamicin.

Hypersensitivity to gentamicin is a contraindication to its use. A history of hypersensitivity or serious toxic reactions to other aminoglycosides may contraindicate use of gentamicin because of the known cross-sensitivity of patients to drugs in this class.

(See BOXED WARNINGS.)

Contains sodium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in asthmatic than in non-asthmatic people.

Aminoglycosides can cause fetal harm when administered to a pregnant woman. Aminoglycoside antibiotics cross the placenta, and there have been several reports of total irreversible bilateral congenital deafness in children whose mothers received streptomycin during pregnancy. Serious side effects to mother, fetus or newborn have not been reported in the treatment of pregnant women with other aminoglycosides. Animal reproduction studies conducted on rats and rabbits did not reveal evidence of impaired fertility or harm to the fetus due to gentamicin sulfate.

It is not known whether gentamicin sulfate can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. If gentamicin is used during pregnancy or if the patient becomes pregnant while taking gentamicin, she should be apprised of the potential hazard to the fetus.

To report SUSPECTED ADVERSE REACTIONS, contact Fresenius Kabi USA, LLC at 1-800-551-7176 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

In the event of overdosage or toxic reactions, hemodialysis may aid in the removal of gentamicin from the blood, especially if renal function is, or becomes, compromised. The rate of removal of gentamicin is considerably lower by peritoneal dialysis than it is by hemodialysis.

Gentamicin injection may be given IM or IV. The patient's pretreatment body weight should be obtained for calculation of correct dosage. The dosage of aminoglycosides in obese patients should be based on an estimate of the lean body mass. It is desirable to limit the duration of treatment with aminoglycosides to short term.

PATIENTS WITH NORMAL

RENAL FUNCTION

Gentamicin Injection, USP, containing gentamicin 40 mg per mL is supplied as follows:

Also available, Gentamicin Injection (Pediatric), 20 mg per 2 mL (10 mg per mL), supplied in 2 mL (20 mg) vials in packages of 25. Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].

The container closure is not made with natural rubber latex.

PREMIERProRx^® is a registered trademark of Premier Healthcare Alliance, L.P., used under license.

Manufactured by:
Fresenius Kabi
Lake Zurich, IL 60047

www.fresenius-kabi.com/us

451333C

Revised: October 2023

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NDC 63323-010-42       PRX1020

Gentamicin Injection, USP

800 mg per 20 mL

(40 mg per mL*)

*Gentamicin equivalent

For intramuscular or intravenous use.

MUST BE DILUTED FOR IV USE.

20 mL Multiple Dose Vial

Rx only

NDC 63323-010-95       PRX1020

Gentamicin Injection, USP

800 mg per 20 mL

(40 mg per mL*)

*Gentamicin equivalent

For intramuscular or intravenous use.

MUST BE DILUTED FOR IV USE.

25 X 20 mL

Multiple Dose Vials Rx only

NDC 63323-010-41       PRX1002

Gentamicin Injection, USP

80 mg per 2 mL

(40 mg per mL*)

*Gentamicin equivalent

For IM or IV Use.

MUST BE DILUTED FOR IV USE.

2 mL Multiple Dose Vial Rx only

NDC 63323-010-94       PRX1002

Gentamicin Injection, USP

80 mg per 2 mL

(40 mg per mL*)

*Gentamicin equivalent

For intramuscular or intravenous use.

MUST BE DILUTED FOR IV USE.

25 X 2 mL

Multiple Dose Vials Rx only