Fecal microbiota transplantation (FMT) involves transferring stool from a healthy donor into a patient to treat recurrent Clostridium difficile (C. diff) infection. FMT has been used in China since the 4th century and the FDA approved its use for C. diff in 2013. C. diff affects over 250,000 people annually in the US and causes diarrhea, dehydration, and even death. The FMT procedure introduces donor stool into the patient's GI tract via enema or capsules to reestablish healthy gut bacteria and clear the C. diff infection, with over 90% success rates reported. Candidates usually have multiple relapses of C. diff despite antibiotic treatment.