Tobramycin Dosage

Usual Adult Dose for Bacterial Infection

1.5 to 2 mg/kg loading dose, followed by 1 to 1.7 mg/kg IV or IM every 8 hours, or 5 to 7 mg/kg IV every 24 hours
Duration: 7 to 21 days, depending on the nature and severity of the infection
Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Adult Dose for Bacteremia

1.5 to 2 mg/kg loading dose, followed by 1 to 1.7 mg/kg IV or IM every 8 hours or 5 to 7 mg/kg IV every 24 hours
Duration: 14 days, depending on the site, nature and severity of the bacteremia
Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Adult Dose for Burns - External

2 to 2.5 mg/kg loading dose, followed by 1.7 to 2 mg/kg IV every 8 hours
Duration: 10 to 14 days, depending on the nature and severity of the infection

Usual Adult Dose for Cystic Fibrosis

IV: 5 to 10 mg/kg/day IV in 2 to 4 divided doses or 10 to 15 mg/kg/day IV in 3 to 4 divided doses; alternatively, 7 to 15 mg/kg IV every 24 hours has been used
Duration: 14 to 21 days, depending on the nature and severity of the infection and improvement of pulmonary function

Solution for inhalation:
Initial dose: 300 mg via nebulizer over approximately 15 minutes twice daily (every 12 hours) for 28 days
Maintenance dose: Administer in alternating cycles of 28 days on and 28 days off. If patient is on multiple therapies, the following order of administration is recommended: Bronchodilator, chest physiotherapy, other inhaled medications, and lastly, tobramycin solution.

Usual Adult Dose for Endocarditis

1.5 to 2 mg/kg loading dose, followed by 1 to 1.7 mg/kg IV every 8 hours for the first 2 weeks
Duration: Antibiotic therapy for enterococcal endocarditis should be continued for 4 to 6 weeks and for more than 6 weeks in patients with Gram-negative endocarditis, depending on the nature and severity of the infection.

Usual Adult Dose for Febrile Neutropenia

2 mg/kg loading dose, followed by 1.7 mg/kg IV every 8 hours
Duration: Once the patient is stable, afebrile for 24 hours, and the absolute neutrophil count is greater than 500/mm3, oral antibiotics may be substituted if antibiotic therapy is to be continued.

Usual Adult Dose for Intraabdominal Infection

2 mg/kg loading dose, followed by 1.7 mg/kg IV every 8 hours or 5 mg/kg IV every 24 hours
Duration: 14 days, depending on the nature and severity of the infection
Less toxic antibiotics may be substituted once the patient is stable for at least 48 hours.

Usual Adult Dose for Meningitis

IV or IM: 2 mg/kg loading dose, followed by 1.7 mg/kg IV or IM every 8 hours
Duration: Parenteral therapy should be continued for at least one week after the patient becomes afebrile and cerebrospinal fluid normalizes.

Intracerebroventricular: 4 to 8 mg intracerebroventricularly (preservative-free formulation) up to every 24 hours, in addition to parenteral antibiotic therapy
Subsequent doses should be based on the CSF concentration.

Usual Adult Dose for Osteomyelitis

1.5 to 2 mg/kg loading dose, followed by 1 to 1.7 mg/kg IV or IM every 8 hours or 5 to 7 mg/kg IV every 24 hours
Duration: 4 to 6 weeks, depending on the nature and severity of the infection
Chronic osteomyelitis may require an additional 1 to 2 months of oral antibiotics. Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Adult Dose for Peritonitis

Intravenous: 2 mg/kg loading dose, followed by 1.7 mg/kg IV every 8 hours or 5 mg/kg IV every 24 hours
Duration: 14 days, depending on the nature and severity of the infection
Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Intraperitoneal in CAPD patients: 0.6 to 0.75 mg/kg intraperitoneally once daily or 16 to 20 mg per every 2 L dialysate

Usual Adult Dose for Pneumonia

2 mg/kg loading dose, followed by 1.7 mg/kg IV or IM every 8 hours or 5 mg/kg IV every 24 hours
Duration: 14 to 21 days, depending on the nature and severity of the infection
Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Adult Dose for Pyelonephritis

2 mg/kg loading dose, followed by 1.7 mg/kg IV every 8 hours or 5 mg/kg IV every 24 hours
Duration: 7 to 14 days, depending on the nature and severity of the infection
Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Adult Dose for Sepsis

2 mg/kg loading dose, followed by 1.7 mg/kg IV every 8 hours or 5 to 7 mg/kg IV every 24 hours
Duration: 10 to 14 days, depending on the nature and severity of the infection
A longer duration may be necessary in immunocompromised or neutropenic patients.

Usual Adult Dose for Shunt Infection

4 to 8 mg intracerebroventricularly (preservative-free formulation) up to every 24 hours, in addition to parenteral antibiotic therapy
Subsequent doses should be based on the CSF concentration. Shunt removal is usually necessary to achieve a cure.

Usual Adult Dose for Skin or Soft Tissue Infection

1.5 to 2 mg/kg loading dose, followed by 1 to 1.7 mg/kg IV or IM every 8 hours or 5 to 7 mg/kg IV every 24 hours
Duration: 10 to 14 days, or until 3 days post acute inflammation, depending on the nature and severity of the infection
For severe infections, such as diabetic soft tissue infections, 14 to 21 days of therapy may be required. Limiting the duration of tobramycin therapy may help limit toxicity. Once the patient is stable for at least 48 hours, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Adult Dose for Tularemia

1.5 to 2 mg/kg loading dose, followed by 1 to 1.7 mg/kg IV or IM every 8 hours or 5 to 7 mg/kg IV every 24 hours
Duration: 10 to 14 days, depending on the nature and severity of the infection
Once the patient's condition improves, less toxic intravenous or oral antibiotic therapy may be considered according to microbiology sensitivity data.

Usual Pediatric Dose for Bacterial Infection

Preterm neonate, 999 g or less: 3.5 mg/kg IV or IM every 24 hours
0 to 4 weeks, 1199 g or less: 2.5 mg/kg IV or IM every 18 to 24 hours
7 days or less, 1200 g or more: 2.5 mg/kg IV or IM every 12 hours
8 days to 4 weeks, 1200 to 2000 g: 2.5 mg/kg IV or IM every 8 to 12 hours
8 days to 4 weeks, 2001 g or more: 2.5 mg/kg IV or IM every 8 hours
1 month to 4 years: 1 to 2.5 mg/kg IV or IM every 8 hours
5 years or older: 2 to 2.5 mg/kg IV or IM every 8 hours

Usual Pediatric Dose for Cystic Fibrosis

IV or IM: 2.5 to 3.3 mg/kg every 6 to 8 hours

Solution for Inhalation:
5 years or less: 40 to 80 mg via nebulizer 2 to 3 times daily

6 to 18 years:
Initial dose: 300 mg via nebulizer over approximately 15 minutes twice daily (every 12 hours) for 28 days
Maintenance dose: Administer in alternating cycles of 28 days on and 28 days off. If patient is on multiple therapies, the following order of administration is recommended: Bronchodilator, chest physiotherapy, other inhaled medications, and lastly, tobramycin solution.

Renal Dose Adjustments

Dosage should be adjusted in renal insufficiency. Various nomograms and methods have been proposed for determining the dosage in renally impaired adult patients - reduced doses at fixed intervals or normal doses at prolonged intervals. Regimens are ideally based on individualized pharmacokinetic dosing.

Adults:
The following adjustments to the maintenance dose have been suggested for adults (modified from Sarubbi and Hull, 1978):
CrCl 70 to 80 mL/min: 76% to 91% of the loading dose every 8 to 12 hours
CrCl 60 to 70 mL/min: 71% to 88% of the loading dose every 8 to 12 hours
CrCl 50 to 60 mL/min: 65% to 84% of the loading dose every 8 to 12 hours
CrCl 40 to 50 mL/min: 72% to 92% of the loading dose every 12 to 24 hours
CrCl 30 to 40 mL/min: 63% to 92% of the loading dose every 12 to 24 hours
CrCl 20 to 30 mL/min: 50% to 81% of the loading dose every 12 to 24 hours
CrCl 10 to 20 mL/min: 34% to 75% of the loading dose every 12 to 24 hours
CrCl 9 mL/min or less: 21% to 47% of the loading dose every 24 hours or a one time loading dose with subsequent doses based on serum concentrations, estimated clearance and the patient's condition

Adults, extended-interval dosing (dose and interval adjustment):
CrCl 80 mL/min or more: 5 to 7 mg/kg every 24 hours
CrCl 60 to 79 mL/min: 4 to 5.5 mg/kg every 24 hours
CrCl 50 to 59 mL/min: 3.5 to 5 mg/kg every 24 hours
CrCl 40 to 49 mL/min: 2.5 to 3.5 mg/kg every 24 hours
CrCl 30 mL/min: 2 to 2.8 mg/kg every 24 hours
CrCl 20 mL/min: 4 to 5 mg/kg every 48 hours
CrCl 10 mL/min: 3 to 4 mg/kg every 48 hours

Adults, extended-interval dosing (constant dose with interval adjustment):
CrCl 61 mL/min or more: 7 mg/kg every 24 hours
CrCl 40 to 60 mL/min: 7 mg/kg every 36 hours
CrCl 20 to 40 mL/min: 7 mg/kg every 48 hours; monitor serum levels
CrCl 19 mL/min or less: 7 mg/kg once; repeat when trough level is less than 1 mcg/mL

Inhalation:
If nephrotoxicity is suspected, therapy should be discontinued until tobramycin serum concentrations fall below 2 mcg/mL.

Liver Dose Adjustments

No adjustment recommended

Dose Adjustments

Parenteral: In obese patients, the appropriate parenteral dose may be calculated by using the estimated lean body weight plus 40% of the excess as the basic weight on which to figure mg/kg.

Inhalation: No dosage adjustments are made.

Precautions

Parenteral: It is desirable to limit the duration of treatment with aminoglycosides to short term. To prevent increased toxicity due to excessive blood levels, dosage should not exceed 5 mg/kg/day unless serum levels are monitored. With treatment more than 10 days, monitoring of renal, auditory, and vestibular functions is recommended.

In patients with extensive burns, altered pharmacokinetics may result in reduced serum levels of aminoglycosides. In such patients treated with tobramycin, measurement of serum levels is recommended as a basis for dosage adjustment.

Inhalation: Safety and efficacy have not been established in patients with FEV(1) less than 25% or greater than 75% predicted, or patients colonized with Burkholderia cepacia.

Dialysis

Hemodialysis: Tobramycin is 30% removed during hemodialysis after parenteral administration. Doses should be administered following dialysis.

Hemodialysis and peritoneal dialysis: One time loading dose, with subsequent doses based on serum concentrations, estimated clearance and the patient's condition.

Pediatric hemodialysis patients:
1 month or older: 1.25 to 1.75 mg/kg/dose IV after dialysis

Other Comments

It is desirable to measure periodically both peak and trough serum levels of tobramycin when feasible during therapy to assure adequate but not excessive drug levels. When monitoring peak levels after IM or IV administration, dosage should be adjusted so that prolonged levels greater than 12 mcg/mL are avoided. When monitoring trough levels (just prior to the next dose), dosage should be adjusted so that levels greater than 2 mcg/mL are avoided. The usual duration of treatment for all patients is 7 to 10 days. In difficult and complicated infections, a longer course of therapy may be necessary.

Intravenous tobramycin should be infused over 20 to 60 minutes.

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