Colistimethate Sodium
Colistimethate sodium is a polymyxin-class antibiotic used to treat serious gram-negative bacterial infections. It is most commonly administered via inhalation for chronic respiratory infections, particularly Pseudomonas aeruginosa in patients with cystic fibrosis, and may also be given intravenously for multi-drug resistant infections when other antibiotics are ineffective.
An inhaled or intravenous polymyxin antibiotic used primarily for resistant gram-negative infections, especially in cystic fibrosis patients.
Key facts at a glance
- RxNorm
- 48305
- Generic
- Colistimethate Sodium
- Class
- pin-variant
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Treatment of chronic respiratory infections caused by gram-negative bacteria, particularly Pseudomonas aeruginosa in patients with cystic fibrosis; also used for multi-drug resistant gram-negative infections when other antibiotics are not effective.
As a polymyxin antibiotic, it binds to the bacterial cell membrane and disrupts its structure, causing increased permeability and cell death in susceptible gram-negative bacteria.
Requires careful monitoring due to potential nephrotoxicity (kidney damage) and neurotoxicity; dosage adjustments may be needed for patients with kidney impairment. Inhaled form may cause bronchospasm. Use is typically reserved for situations where other antibiotics are ineffective due to resistance concerns.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy