The brand name for Tacrolimus is Protopic. You may have heard of it. It is also an immunosuppressant like steroids but works through a different mechanism that I don't know of off the top of my head. But, it has been used for the prevention of organ transplant rejection. It has worked for some, but not myself. I have never had a lip swab, and that's something I would be interested in. Have any of you done this??? Please respond. Thanks!