Common Medications Linked to Years-Long Disruption of Gut Health, Study Finds
A new study published today reveals that a wide range of prescription medications, beyond antibiotics, can significantly alter the gut microbiome, with effects potentially lasting for years after use—a finding that could reshape how doctors consider long-term patient health.
Researchers analyzing data from 2,509 adults participating in the Estonian microbiome cohort found that antidepressants, beta-blockers, stomach acid reducers, and anti-anxiety drugs, among others, were associated with lasting changes in the composition of gut bacteria. The study, appearing in the American Society for Microbiology’s mSystems journal, utilized stool samples and electronic health records to assess the impact of 186 different drugs. “The methodology was robust, and convincingly linked changes in gut microbiome to medication uses, but this was not a controlled trial,” explained Dr. Babak Firoozi, a board-certified gastroenterologist at MemorialCare Orange Coast Medical Center. “There are far too many variables that cannot be accounted for.”
The research team discovered that 167 drugs affected the microbiome in some way, with 78 demonstrating long-term effects. Notably, benzodiazepines, commonly prescribed for anxiety, appeared to have the most substantial negative impact. Even within drug classes, variations were observed; for example, alprazolam (Xanax) had a broader effect than diazepam (Valium). A disrupted gut microbiome, or dysbiosis, has been linked to a growing number of chronic conditions, including inflammatory bowel disease, type 2 diabetes, and autoimmune disorders. The longer a medication was taken, and the more medications used concurrently, the greater the observed effect on the microbiome.
Study co-author Elin Οrg, PhD, head of the Microbiome Research Group at University of Tartu, emphasized the importance of considering the microbiome when making treatment decisions. “If two drugs work equally well, doctors may opt for the one that has a smaller impact on the gut microbiome,” she stated. Experts recommend following a high-fiber, low-fat diet and regular exercise to support overall gut health, and only taking medications as prescribed and for the shortest duration necessary. Further research is planned to investigate the specific mechanisms by which these medications impact the gut and to explore potential interventions to mitigate negative effects.
