Oral activated charcoal (OAC), a potent adsorbent with no systemic absorption, has been used for centuries to treat poisoning. Recent studies have suggested its potential efficacy in protecting the colonic microbiota against detrimental effects of antibiotics. In a dose-finding safety and feasibility clinical trial, 12 healthy volunteers not receiving antibiotics drank 4 different preparations made of 2 possible OAC doses (12 or 25 grams) mixed in 2 possible solutions (water or apple juice), 3 days a week for 2 weeks. Pre- and post-OAC stool samples underwent 16S rRNA gene sequencing and exact amplicon sequence variants were used to characterize the colonic microbiota. The preferred preparation was 12 grams of OAC in apple juice, with excellent safety and tolerability. OAC did not influence the gut microbiota in our healthy volunteers. These findings provide the critical preliminary data for future trials of OAC in patients receiving antibiotics.
Bibliographical noteFunding Information:
This work was supported by a University of Minnesota Medical School pilot award to A.R. and a National Institutes of Health’s National Center for Advancing Translational Sciences (KL2TR002492). Conventional statistical analysis was performed with Biostatistics Shared Resource of the University of Minnesota Masonic Cancer Center, supported by NIH/NCI grant P30CA07759. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health’s National Center for Advancing Translational Sciences. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. We thank Sharon Lopez for DNA extraction. Sequence data were processed and analyzed using the resources of the Minnesota Supercomputing Institute.
© 2022 Rashidi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Anti-Bacterial Agents/adverse effects
- Feasibility Studies
- Gastrointestinal Microbiome
- Healthy Volunteers
- RNA, Ribosomal, 16S/genetics
PubMed: MeSH publication types
- Clinical Trial
- Journal Article
- Research Support, Non-U.S. Gov't
- Research Support, N.I.H., Extramural