The human gut microbiota plays a crucial role in maintaining host health and modulating pharmacokinetics. Growing evidence indicates that probiotic preparations, which contain live microorganisms conferring health benefits to the host, can influence the absorption, metabolism, and excretion of various drugs. These effects may be mediated through multiple mechanisms, including modification of intestinal enzyme activity, alteration of gut permeability, competition for transporters, or indirect modulation of immune and inflammatory pathways. Despite the increasing clinical use of probiotics, their potential interactions with therapeutic agents remain poorly characterized, and the clinical relevance of these interactions is largely unexplored.

This Research Topic aims to provide a comprehensive understanding of how probiotic preparations affect drug concentrations and the incidence or severity of adverse effects. Both beneficial and detrimental interactions deserve attention: while certain probiotics may mitigate antibiotic-associated diarrhea or chemotherapy-induced mucositis, others could potentially alter systemic drug exposure and compromise therapeutic efficacy or safety. The complexity of these interactions underscores the need for interdisciplinary research integrating microbiology, pharmacology, clinical medicine, and systems biology.

We invite submissions that explore the mechanistic, preclinical, and clinical aspects of probiotic–drug interactions. Relevant studies may include, but are not limited to, the following sub-topics:

1. Mechanistic investigations of how probiotics modulate drug metabolism via microbial enzymes.

2. Experimental and clinical studies assessing changes in pharmacokinetic parameters (Cmax, AUC, clearance, etc.) associated with probiotic co-administration.

3. Investigations into the impact of probiotics on drug-induced organ toxicity, gastrointestinal side effects, or alterations in host immunity.

4. Metabolomic and microbiome-based analyses elucidating the bidirectional relationship between probiotic supplementation and xenobiotic metabolism.

5. Clinical trials evaluating the safety, efficacy, and optimal timing or formulation of probiotics when combined with antimicrobial agents, immunosuppressants, anticancer drugs, or other pharmacological classes.

This Research Topic welcomes the following articles types: FAIR² Data, Hypothesis and Theory, Methods, Mini Review, Opinion, Original Research, Perspective, Review, Systematic Review, Technology and Code, summarizing current evidence, as well as computational or in silico approaches that model microbiota-mediated drug transformations.

Furthermore, studies addressing regulatory and clinical implications of probiotic–drug interactions are encouraged, especially those highlighting the need for individualized therapeutic strategies considering gut microbial composition.

By consolidating insights from basic science to clinical practice, this collection will advance our understanding of the dynamic interplay between probiotics and pharmacotherapy. Ultimately, elucidating these interactions may lead to improved therapeutic outcomes, reduced adverse effects, and the rational design of microbiome-based adjunctive therapies. We hope this Research Topic will foster collaboration among microbiologists, pharmacologists, and clinicians to bridge the gap between microbiome science and precision medicine.

Are you interested in contributing a manuscript to this Research Topic?

The Impact of Probiotics on Antimicrobial Drugs