Overview
- An eight-year Nature Medicine study of nearly 15,000 adults in Sweden links prior antibiotic use to persistent changes in gut bacterial composition.
- Researchers found that roughly 10–15% of species remained altered four to eight years after exposure, indicating incomplete recovery.
- Lasting impacts varied by drug class, with clindamycin, flucloxacillin and fluoroquinolones showing the strongest long-term shifts.
- Common options such as penicillin V, amoxicillin and sulfamethoxazole/trimethoprim were associated with little or no durable change in the microbiome.
- The team observed decreases in some health-promoting bacteria and increases in groups tied to metabolic and inflammatory diseases, and they are continuing work to map vulnerable taxa and recovery timelines.