Colistimethate Sodium

Colistimethate sodium (colistin polymyxin E) is a polymyxin antibiotic administered parenterally or by inhalation. It acts as a surfactant that penetrates and disrupts the bacterial outer and cytoplasmic membranes of Gram-negative bacteria, causing leakage of intracellular contents and cell death. Due to risk of nephrotoxicity and neurotoxicity, its systemic use is generally reserved for multi-drug resistant infections.

Dosage by Body Weight

Parenteral dosage is based on Colistin Base Activity (CBA) or International Units (IU). Pediatric dose with normal renal function is typically 2.5 to 5 mg/kg/day of CBA (75,000 to 150,000 IU/kg/day) divided into 3 doses administered intravenously. Daily maximum is typically 5 mg/kg/day of CBA. Strict dose adjustment is required in patients with renal impairment.

  1. Body Weight
    Below 5 kg
    Dose
    Not routine
    Frequency
    Use only if prescribed
    Tracking Notes
    Extreme caution required in neonates and infants due to immature renal function. If essential, dose is 2.5 to 5 mg/kg/day CBA divided every 8 to 12 hours with close therapeutic drug monitoring.
  2. Body Weight
    5-7 kg
    Dose
    12.5 mg to 35 mg of Colistin Base Activity (CBA) per day
    Frequency
    Divided every 8 hours
    Tracking Notes
    Corresponds to approximately 2.5 to 5 mg/kg/day of CBA. Monitor renal function closely and maintain adequate hydration.
  3. Body Weight
    8-10 kg
    Dose
    20 mg to 50 mg of Colistin Base Activity (CBA) per day
    Frequency
    Divided every 8 hours
    Tracking Notes
    Administer intravenously over 30 to 60 minutes. Monitor serum creatinine and urine output.
  4. Body Weight
    11-15 kg
    Dose
    27.5 mg to 75 mg of Colistin Base Activity (CBA) per day
    Frequency
    Divided every 8 hours
    Tracking Notes
    Adjust dosage down immediately if there is any sign of developing nephrotoxicity or decreased renal clearance.
  5. Body Weight
    16-20 kg
    Dose
    40 mg to 100 mg of Colistin Base Activity (CBA) per day
    Frequency
    Divided every 8 hours
    Tracking Notes
    Do not exceed 5 mg/kg/day of CBA. Ensure serum level monitoring if available, especially during prolonged therapy.

Formulation

Powder for InjectionPowder for Nebuliser SolutionInhalation Powder

Purpose

Treatment of severe acute or chronic infections caused by susceptible Gram-negative bacilli, particularly multidrug-resistant Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii, when other safer alternatives are ineffective or contraindicated.

Generic Name

Colistimethate Sodium

Branded Drug Names

Colistimethate Sodium is listed as a generic drug name. Common branded medicines that may contain the same active ingredient include:

Scheduled Drug

Yes. This medicine should be supplied or used only according to applicable prescription and regulatory requirements.

Alternatives

Disclaimer: This information is for educational purposes only. WHO references and weight bands are simplified for tracking and must not replace medical advice. Always consult with a healthcare professional before starting or changing any medication.