Hello @contentandwell, this is a great post. I have done a brief search myself, and the results are overwhelming. Have you tried searching on PubMeb? A lot of Mayo Clinic doctors publish research and most of them end up on PubMeb. Here is a link to the search results I found using "Herbal teas and transplant patients," https://www.ncbi.nlm.nih.gov/pubmed/?term=herbal+teas+and+transplant+patients. It may give you a few articles to look over, but I will continue to see if I can find more Mayo Clinic sources.