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Updated: Jun 16, 2026
10:49
Antibiotic Dereplication Using the Antibiotic Resistance Platform
Published on: October 17, 2019
[Tetracyclines, sulfonamides, and metronidazole]
Diego Vicente1, Emilio Pérez-Trallero
1Servicio de Microbiología, Hospital Donostia, San Sebastián, Spain.
Enfermedades Infecciosas Y Microbiologia Clinica
|January 26, 2010
Summary
Tetracyclines and metronidazole are effective antibiotics that inhibit bacterial growth. Despite past resistance issues, tetracyclines like doxycycline and tigecycline are regaining importance, while sulfonamides are rarely used.
Area of Science:
- Pharmacology
- Microbiology
- Infectious Diseases
Background:
- Tetracyclines, natural or semisynthetic, inhibit bacterial protein synthesis and are bacteriostatic with broad-spectrum activity.
- Acquired resistance previously limited tetracycline use, but new components are restoring their status.
- Doxycycline is a WHO essential drug; tigecycline offers broader activity against multiresistant organisms.
Purpose of the Study:
- To review the current status and applications of tetracyclines, sulfonamides, and metronidazole in antibacterial therapy.
- To highlight the resurgence of tetracyclines due to new formulations and their role in treating resistant infections.
- To discuss the limited use of sulfonamides and the established efficacy of metronidazole.
Main Methods:
- Literature review of established antibiotics.
- Analysis of antibiotic mechanisms of action and spectrum of activity.
- Evaluation of historical and current clinical relevance based on resistance patterns and efficacy.
Main Results:
- Tetracyclines are regaining clinical importance, with doxycycline and tigecycline showing significant utility.
- Sulfonamides have limited use due to toxicity and resistance.
- Metronidazole is highly effective against anaerobic bacteria, microaerophilic bacteria, and protozoa.
Conclusions:
- Tetracyclines, particularly doxycycline and tigecycline, are valuable broad-spectrum antibiotics for various infections.
- Metronidazole remains a critical treatment for anaerobic and parasitic infections.
- The clinical utility of antibiotics is continually reassessed based on evolving resistance and therapeutic advancements.
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