Parenteral Manual

Gentamicin sulphate

Disclaimer: Official controlled document is the CHEO online copy. It is the responsibility of user to ensure that any paper copy version is the same as the online version before use.

Alternate Name(s): 
Aminoglycoside antibiotic
Original Date: 
August 2005
Revised Date: 
December 2019
  • Antibiotic for the treatment of serious infections caused by susceptible bacteria (primarily gram negative)
Reconstitution and Stability: 
  • Stable at room temperature
  • Available as a 40 mg/mL solution
  • Vial stable 30 days refrigerated once punctured
  • Diluted solutions stable 48 hours refrigerated or at room temperature

- Solutions Compatible: dextrose concentrations up to D10W, 0.9% NaCl, ringer's solution

- Additives/Above Cassette Compatible: clindamycin

- Y-site Compatible: heparin (0.5 - 1 unit/mL), morphine, KCl, TPN (amino acids/dextrose)

- Incompatible: heparin (greater thatn 1 unit/mL), azithromycin, furosemide, propofol; Do not mix with beta lactam antibiotics. Flush line well between administration of beta lactams and aminoglycoside antibiotics .


(For approved routes of administration by nursing personnel, refer to Policy for the Administration of Intravenous Medications.)

IV Direct NO
IV Intermittent Infusion

Usual dilution: 5 mg/mL
- 1 mg/mL for dose less than or equal to 10 mg
Infusion time: 30 minutes

IV Continuous Infusion NO



(For neonatal dosages, refer to Neonatal IV Drug Manual.)


Traditional dosing : 7.5 mg/kg/day divided Q8H. Maximum 120 mg/dose if no previous levels

Single daily dosing : 7 mg/kg/day Maximum 360 mg / dose if no previous levels

Combination therapy for synergy in selected infections : 3 mg/kg/day divided Q8H  Maximum 80 mg/dose before levels


 Febrile Neutropenia Pediatric/Adolescent:

Once daily dosing: 7.5 mg/kg/dose - NO MAXIMUM DOSE
-Calculate dose based on actual body weight unless the patient weighs greater than or equal to 125% of ideal body weight, in which case the dose is based on the effective body weight.


Click here to go to Lexicomp online to calculate the Ideal Body Weight.  From this page, type in "ideal body weight "in the lookup box, click on lookup tab and choose either Ideal Body Weight:  Adult for patients over 60 inches or Ideal Body Weight:  Pediatric for patients less than 60 inches (152.4 cm)


Dose interval adjustment in renal impairment with traditional dosing:       

CrCl 40-60 mL/minute: Administer Q 12 hours

CrCl 20-39 mL/minute: Administer Q 24 hours

CrCl < 20 mL/minute: Administer normal dose, then monitor levels

Adjust regimen based on serum concentrations

Potential hazards of parenteral administration: 
  • Hypersensitivity reactions [urticaria, rash, hives, pruritis, fever (rare)]
  • Ototoxicity (vertigo, hearing loss, tinnitus, dizziness)
  • Nephrotoxicity (proteinuria, reduction in GFR, elevated serum creatinine)
  • Potential for neuromuscular blockade (rare)

Adverse effects are potentiated by other ototoxic or nephrotoxic drugs

  • Apnea may result when combined with anesthetics or other neuromuscular blocking drugs
  • Maintain good hydration, baseline serum creatinine and repeat once weekly, caution in patients with impaired renal function
  • An audiology consult is recommended if IV aminoglycoside therapy is expected to continue for 14 days.  Repeat every 7 days if therapy continues.

Therapeutic Drug Monitoring:

When checking level, administer next dose as scheduled.  Do not wait for levels to be reported unless otherwise advised

Traditional Dosing: Therapeutic Serum Concentration
- Initial levels on Day 3 and repeat once weekly

PRE (Trough): less than 2 mg/L

POST (Peak):
5 - 10 mg/L (gram negative infections)

Traditional Dosing : Sampling Time

PRE: 0 - 30 minutes prior to next dose

POST: 30 minutes after end of 30 minute infusion

Single Daily Dosing:

 -  Initial level on Day 3 and repeat once weekly

Measure PRE only
-  0 - 30 minutes prior to next dose
-  less than 0.3 mg/L

Combination therapy for synergy:
- Initial level on Day 3 and repeat once weekly
Measure PRE only
- 0 - 30 minutes prior to next dose
- less than 0.3 mg/L

The information contained on this website is provided for informational purposes only, as a guide to assist physicians, nurses and other healthcare providers in deciding on the appropriate care required for a particular patient. At all times, physicians, nurses and other healthcare providers must exercise their independent clinical judgment, based on their knowledge, training and experience, taking into account the specific facts and circumstances of each patient, when deciding on the appropriate course of investigation and/or treatment to recommend in a particular clinical situation.

CHEO has made every effort to ensure that the information contained on this website is as current and accurate as possible. However, changes can occur due to ongoing research and the constant influx of new information. Where possible, hospitals and healthcare practitioners should verify the information before acting on it.

Reliance on any information in this website is at the user's own risk. CHEO is not responsible or liable for any harm, loss or other consequences from the use or misuse of the information on this website.