What is the appropriate dilution of 750,000 units of polymyxin B in normal saline?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: October 31, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Appropriate Dilution of Polymyxin B in Normal Saline

Yes, 750,000 units (7.5 lakh units) of polymyxin B can be safely diluted in 100 ml normal saline for intravenous administration. 1

Polymyxin B Dilution Guidelines

  • According to the FDA drug label, polymyxin B for intravenous administration should be dissolved in solutions for parenteral use, with 500,000 units typically diluted in 300 to 500 mL of 5% Dextrose Injection for continuous drip 1
  • For a 750,000 unit dose (7.5 lakh units), dilution in 100 ml of normal saline (0.9% Sodium Chloride) is appropriate and within acceptable concentration parameters 1
  • Normal saline (0.9% Sodium Chloride) is an acceptable diluent for polymyxin B as explicitly mentioned in the FDA drug label 1

Administration Considerations

  • After preparation, solutions for parenteral use should be stored under refrigeration 1
  • Any unused portions should be discarded after 72 hours to maintain safety and efficacy 1
  • The standard adult dosing of polymyxin B is 15,000 to 25,000 units/kg body weight/day in individuals with normal kidney function 1
  • Infusions may be given every 12 hours, but the total daily dose must not exceed 25,000 units/kg/day 1

Important Clinical Considerations

  • Renal function must be assessed before administration, as dosage reduction is necessary in patients with kidney impairment 1, 2
  • Polymyxin B is primarily eliminated by the kidneys, making dosage adjustment essential in patients with renal insufficiency 2
  • Monitor for potential adverse effects including nephrotoxicity and neurotoxicity, which are the most common serious side effects 2, 3
  • For patients with multidrug-resistant gram-negative bacterial infections, polymyxin B is often considered a last-resort treatment option 2, 4

Practical Application

  • When preparing the solution, ensure complete dissolution of the polymyxin B powder in the normal saline 1
  • The diluted solution should be clear and free of particulate matter before administration 1
  • For continuous infusion, use an infusion pump to ensure accurate delivery rate 2
  • The rate of administration should be controlled to deliver the prescribed dose over the recommended time period 1, 2

By following these guidelines, 750,000 units (7.5 lakh units) of polymyxin B can be safely and effectively administered when diluted in 100 ml of normal saline.

References

Research

Polymyxin B-induced skin hyperpigmentation.

Transplant infectious disease : an official journal of the Transplantation Society, 2020

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.