In a groundbreaking new study, conducted within the framework of the FWF-funded Cluster of Excellence “Microbiomes drive Planetary Health”, scientists from the University of Vienna, in collaboration with the University of Southampton, Aalborg University and Boston University, have revealed that the widely prescribed Parkinson’s disease drug entacapone significantly disrupts the human gut microbiome by inducing iron deficiency. The study, published in Nature Microbiology, provides new insights into the often-overlooked impact of human-targeted drugs on the microbial communities that play a critical role in human health.