New research by a team of German scientists indicates that antibiotics aren't the only drugs that affect the gut microbiome. "This shift in the composition of our gut bacteria contributes to drug side-effects, but might also be part of the drugs' beneficial action." Human-targeted drugs, antimicrobial impactsFor the study, the researchers monitored the growth of 40 representative isolates of human gut bacteria upon treatment with 1,079 compounds. But 27% of the non-antibiotic drugs tested also affected bacterial growth, including 24% of the human-targeted drugs. And further study of how these drugs impact the gut microbiome could lead to improvements that reduce side effects and improve efficacy.