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Updated: Jun 24, 2026

Antibiotic Dereplication Using the Antibiotic Resistance Platform
10:49

Antibiotic Dereplication Using the Antibiotic Resistance Platform

Published on: October 17, 2019

[Aminoglycosides and polymyxins]

José Molina1, Elisa Cordero, Julián Palomino

  • 1Servicio de Enfermedades Infecciosas, Hospitales Universitarios Virgen del Rocío, Sevilla, España.

Enfermedades Infecciosas Y Microbiologia Clinica
|March 24, 2009
PubMed

Insights

Older antibiotics like aminoglycosides and polymyxins are being reconsidered for multidrug-resistant gram-negative infections. Once-daily aminoglycoside dosing and new polymyxin formulations reduce toxicity, making them viable again.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pharmacology

Context:

  • Rising prevalence of multidrug-resistant (MDR) gram-negative bacilli.
  • Re-evaluation of older antimicrobial agents due to resistance.
  • Need for effective treatments against challenging infections.

Purpose:

  • To review the re-emergence and current clinical utility of older antimicrobials.
  • To assess the impact of modified dosing and formulations on the safety and efficacy of aminoglycosides and polymyxins.
  • To evaluate their role in treating infections caused by MDR gram-negative bacilli.

Summary:

  • Aminoglycosides, once-daily administration has reduced toxicity, allowing their reintroduction. However, combination therapy with beta-lactams offers no added benefit, and specific indications for once-daily dosing are not universally supported.
  • Newer formulations of polymyxins have significantly decreased toxicity. Colistin shows favorable outcomes in MDR gram-negative infections, whether used alone or in combination.
  • Further research is needed to fully elucidate the pharmacokinetics and effectiveness of these agents.

Impact:

  • Provides insights into the evolving treatment landscape for MDR gram-negative infections.
  • Highlights the renewed importance of older antibiotics with improved safety profiles.
  • Informs clinical decision-making regarding the use of aminoglycosides and polymyxins against resistant pathogens.

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