Reviewed on 8/25/2021

What Is Tobramycin and How Does It Work?

Tobramycin is a prescription aminoglycoside antibiotic used as treatment against Gram-positive and Gram-negative bacteria.

Tobramycin is available under the following different brand names: Nebcin injection.

Dosage of Tobramycin

Adult and Pediatric Dosages:

Injectable solution

  • 10 mg/ml
  • 40 mg/ml

Dosage Considerations – Should be Given as Follows:

Bacterial infections

  • 3-6 mg/kg/day intravenously/intramuscularly divided every 8 hours OR
  • 4-7 mg/kg/dose intravenously/intramuscularly each day

Renal Impairment


  • Creatinine Clearance over 60 mL/min: every 8 hours
  • Creatinine Clearance 40-60 mL/min: every 12 hours
  • Creatinine Clearance 20-40 mL/min: every 24 hours
  • Creatinine Clearance 10-20 mL/min: every 48 hours
  • Creatinine Clearance under 10 mL/min: ever 72 hours
  • Following dialysis in ESRD


  • Children under 5 years old: 2.5 mg/kg/dose intravenously/intramuscularly every 8 hours
  • Children 5 years and older: 2-2.5 mg/kg/dose intravenously/intramuscularly every 8 hours
  • Hemodialysis: 1.25-1.75 mg/kg/dose post dialysis


Adult and pediatric:

  • Peak and trough concentrations, renal and auditory function
  • Life-threatening infection: 8-10 mcg/mL
  • Serious infection: 6-8 mcg/mL
  • Urinary Tract Infections: 4-6 mcg/mL
  • Synergy for infections caused by gram-positive organisms: 3-5 mcg/mL

Cystic Fibrosis


  • Intravenously/intramuscularly: 2.5-3.3 mg/kg every 6-8 hours


  • Less than 30 weeks gestation
  • Infants less than 28 days old: 2.5 mg/kg intravenously/intramuscularly every day
  • Infants 28 days or older: 3 mg/kg intravenously/intramuscularly every day

30-36 week gestation

  • Infants less than 14 days old: 3 mg/kg intravenously/intramuscularly every day
  • Infants 14 days or older: 5 mg/kg/day intravenously/intramuscularly divided every 12 hours

Over 37 week gestation

  • Infants less than 7 days old: 5 mg/kg/day intravenously/intramuscularly divided every 12 hours
  • Infants 7 days or older: 7.5 mg/kg/day intravenously/intramuscularly divided every 8 hours

Other Indications and Uses

May have increased activity against resistant Gram negative

  • Citrobacter Spp., E. coli, P. aeruginosa, Proteus Spp. (indole-positive and negative), Providencia Spp. (including Klebsiella-Enterobacter-Serratia), S. aureus (coagulase-positive and negative)


Fungal Skin Infections: Types, Symptoms, and Treatments See Slideshow

What Are Side Effects Associated with Using Tobramycin?

Side effects of tobramycin include:

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

What Other Drugs Interact with Tobramycin?

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

  • Tobramycin has no known severe interactions with other drugs.
  • Tobramycin has serious interactions with at least 25 different drugs.
  • Tobramycin has moderate interactions with at least 66 different drugs.
  • Tobramycin has mild interactions with at least 72 different drugs.

This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns, or for more information about this medicine.

What Are Warnings and Precautions for Tobramycin?


  • Kidney damage manifested as both bilateral auditory and temporary or permanent hearing loss can occur in patients with preexisting kidney damage and in patients with normal kidney function treated at higher doses and/or for periods longer than those recommended
  • High-frequency deafness usually occurs first and can be detected only by audiometric testing
  • Vertigo may occur and may be evidence of temporary or permanent injury
  • Aminoglycosides are potentially damaging to the kidneys
  • Risk is greater in patients with impaired kidney function and in those who receive high doses or prolonged therapy
  • Rarely, kidney damage may not become apparent until the first few days after cessation of therapy
  • Use with caution in premature infants and neonates because of renal immaturity and the resulting prolongation of serum half-life of the drug
  • Neuromuscular blockade and respiratory paralysis have been reported following parenteral injection, topical instillation (as in orthopedic and abdominal irrigation or local treatment of empyema), and oral use of aminoglycosides, especially when given soon after anesthesia or muscle relaxants
  • If a blockage occurs, calcium salts may reverse these phenomena, but mechanical respiratory assistance may be necessary
  • Avoid concurrent or sequential use of neurotoxic and/or nephrotoxic drugs including other aminoglycosides (amikacin, streptomycin, neomycin, kanamycin, gentamicin, or paromomycin)
  • Cumulative listing of drugs to avoid from all aminoglycoside package inserts includes amphotericin B, bacitracin, cephaloridine, cisplatin, colistin, polymyxin B, vancomycin, and viomycin
  • Avoid potent diuretics (ethacrynic acid, furosemide) because they increased the risk of temporary or permanent hearing loss
  • When administered intravenously, diuretics may enhance aminoglycoside toxicity by altering antibiotic concentrations in serum and tissue
  • This medication contains tobramycin
  • Do not take Nebcin injection if you are allergic to tobramycin or any ingredients contained in this drug

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately


  • Hypersensitivity to tobramycin

Effects of Drug Abuse

  • No information available

Short-Term Effects

  • See "What Are Side Effects Associated with Using Tobramycin?"

Long-Term Effects

  • See "What Are Side Effects Associated with Using Tobramycin?"


  • Concurrency with neuromuscular blockers
  • Aminoglycosides are associated with nephrotoxicity and temporary or permanent hearing loss
  • Kidney impairment
  • Auditory or balance impairment
  • May cause irreversible hearing loss

Pregnancy and Lactation

  • Use tobramycin with caution during pregnancy if benefits outweigh risks
  • Animal studies show risk and human studies are not available or neither animal nor human studies were done
  • Tobramycin enters breast milk
  • Consult your physician if breastfeeding


Bowel regularity means a bowel movement every day. See Answer
Medscape. Tobramycin.
RxList. Tobramycin Monograph.

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