A new randomized clinical trial shows fecal microbiota transplantation (FMT) significantly improved treatment response in adults with depressive episodes when used alongside standard antidepressant medication.
Forty-six adults aged 18-65 received either FMT plus medication or medication alone. After two weeks, the FMT group showed significantly greater reductions in Hamilton Depression Rating Scale scores (p=0.048) and a higher symptom reduction rate (p=0.016).
Microbiological analysis revealed post-treatment increases in Enterococcus, Lactobacillus, Bifidobacterium, and Butyricicoccus. Enterococcus abundance rose significantly (p=0.02) and correlated with depression severity (p=0.030). Baseline levels of Clostridium prausnitzii and Eubacterium rectale were negatively associated with symptom severity.
FMT was well tolerated-with mild, self-limiting adverse events only-and did not disrupt overall microbiota structure. Larger, long-term studies are needed to confirm durability and optimize protocols.