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Polymyxin B: similarities to and differences from colistin (polymyxin E)
Andrea Kwa1, Sofia K Kasiakou, Vincent H Tam
1Singapore General Hospital, Outram Road, 169608, Singapore. andrea.kwa.l.h@sgh.com.sg
Expert Review of Anti-Infective Therapy
|October 5, 2007
Summary
Polymyxin B and colistin are crucial antibiotics for multidrug-resistant infections. This review details their similarities and differences in structure, potency, and clinical use.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Hospital-acquired infections caused by multidrug-resistant gram-negative bacteria are a significant global health threat.
- Effective antibiotic options are dwindling, with few new agents in development.
- Polymyxins, including polymyxin B and colistin (polymyxin E), are among the last-resort treatments.
Purpose of the Study:
- To comprehensively review and compare polymyxin B and colistin.
- To highlight their shared characteristics and distinct properties.
Main Methods:
- Literature review of existing studies on polymyxin B and colistin.
- Comparative analysis of their chemical structures, antimicrobial activity, clinical applications, toxicity profiles, formulations, potency, dosage, and pharmacokinetics.
Main Results:
- Polymyxin B and colistin share similar mechanisms of action, antimicrobial spectra, clinical uses, and toxicity.
- Key differences exist in their chemical structures, available formulations, potency, recommended dosages, and pharmacokinetic properties.
Conclusions:
- Understanding the nuances between polymyxin B and colistin is essential for optimizing their use in clinical practice.
- Further research may elucidate optimal strategies for utilizing these critical last-line antibiotics.
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