By Kelly Young
Edited by Susan Sadoughi, MD, and André Sofair, MD, MPH
Gut microbial diversity may be diminished for up to a year following oral antibiotic use, suggests a small, industry-conducted study published in mBio.
Sixty-six healthy participants in the U.K. and Sweden were randomized to receive placebo or an antibiotic (clindamycin, amoxicillin, ciprofloxacin, or minocycline). They provided saliva and fecal samples before and after receiving antibiotics.
Over the long term, the salivary microbiome was largely undisturbed by antibiotic administration. Meanwhile, microbiome diversity in fecal samples was reduced for up to 4 months in patients receiving clindamycin and up to 12 months in those receiving ciprofloxacin. Specifically, bacteria that produce the short-chain fatty acid butyrate — which is linked to lower inflammation, carcinogenesis, and oxidative stress in the gut — were significantly reduced.
In addition, genetic testing found more genes associated with antibiotic resistance in the fecal samples.
The authors conclude: "Clearly, even a single antibiotic treatment in healthy individuals contributes to the risk of resistance development and leads to long-lasting detrimental shifts in the gut microbiome."