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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
PubMed

Insights

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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