Long-Term Effects of Medications on Gut Microbiome Persist Years After Use

Research from the University of Tartu Institute of Genomics has revealed that medications taken years ago can have enduring effects on the human gut microbiome. By analyzing stool samples and prescription records from over 2,500 participants in the Estonian Biobank, scientists found that many drugs influence microbial composition not only during treatment but also long after discontinuation. The study highlighted that the impact extends beyond antibiotics to include antidepressants, beta-blockers, proton pump inhibitors, and benzodiazepines, all leaving detectable microbial signatures.

Lead researcher Dr. Oliver Aasmets emphasized that most microbiome studies focus solely on current medication use, yet this research demonstrates that past drug intake significantly contributes to individual microbiome variations. Considering drug history is crucial when studying microbiome-disease links. Interestingly, benzodiazepines prescribed for anxiety showed microbiome effects comparable to broad-spectrum antibiotics. Variations within drug classes, such as diazepam versus alprazolam, also influence the extent of microbial disruption.

Follow-up assessments of a subset of participants confirmed that initiating or stopping certain medications causes predictable shifts in microbial composition, suggesting causal relationships. Despite limited sample sizes for some longitudinal data, long-term effects were confirmed for proton pump inhibitors, selective serotonin reuptake inhibitors, and combinations of antibiotics. This comprehensive analysis underscores the importance of factoring in medication history in microbiome research and clinical diagnostics.

These findings are published in the journal mSystems and pave the way for more nuanced understanding of how long-term medication use shapes our microbial ecosystems, potentially affecting health outcomes long after treatment ends.