Fluoroquinolone treatments induce dysbiosis of the intestinal microbiota, resulting in loss of resistance to colonization by exogenous bacteria such as Clostridioides difficile that may cause severe diarrhea in humans and lethal infection in hamsters. We show here that DAV131A, a charcoal-based adsorbent, decreases the intestinal levels of the fluoroquinolone antibiotics levofloxacin and ciprofloxacin in hamsters, protects their intestinal microbiota, and prevents lethal infection by C. difficile .