• Probiotics as Adjunct Therapy in Bacterial Infections: A Systematic Review of Clinical Evidence
  • Mina Shirmohammadpour,1 Arman Taran,2 Bahman Mirzaei,3,*
    1. Department of Microbiology and Virology, Faculty of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
    2. Department of Microbiology and Virology, Faculty of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
    3. Department of Microbiology and Virology, Faculty of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran


  • Introduction: The emergence of antibiotic resistance and dysbiosis associated with antibiotic therapy has driven interest in probiotics as potential adjunctive treatments. Probiotics may enhance immune responses, restore microbial balance, and improve clinical outcomes in bacterial infections. This systematic review aims to evaluate the clinical effectiveness of probiotics as adjunct therapy in the treatment of bacterial infections across various body systems.
  • Methods: Databases including PubMed, Scopus, and Web of Science were systematically searched for clinical trials and meta-analyses published between January 2015 and May 2024. PRISMA guidelines were followed. Studies involving co-administration of probiotics with antibiotics in bacterial infections were included; those focusing on fungal or viral infections were excluded.
  • Results: Out of 953 screened articles, 42 met the inclusion criteria. Clinical trials reported that adjunct probiotic therapy led to reduced symptom severity and shorter recovery time in respiratory tract infections, urinary tract infections, and gastrointestinal infections. Lactobacillus rhamnosus GG and Saccharomyces boulardii were the most commonly used strains. Probiotics showed a significant effect in preventing antibiotic-associated diarrhea and Clostridioides difficile infection. However, strain-specific effects and variations in dosage, duration, and patient populations were reported as limitations.
  • Conclusion: Probiotic supplementation, when used alongside antibiotics, shows promising benefits in managing bacterial infections and mitigating treatment-related side effects. More standardized, large-scale trials are needed to determine optimal strains and regimens.
  • Keywords: Probiotics, Adjunct Therapy, Bacterial Infections, Clinical Trials, Antibiotic Resistance, Gut Micro