Hi. I take tacrolimus and have since 1990. I was in clinical trial for fk 506, now tacrolimus. Prednisone for first 3 months. All was great until 2015 when I experienced major stress, husband diagnosed with cancer and 3 weeks later my mother passed. My numbers were in normal range but for 25 yrs my numbers were same. They rose despite being in normal range. Ggt is. Got biopsy and diagnosed with rejection, ductopenia, and pancreatic cyst impinging on bile duct. Dr increased tacrolimus to high level for 3 years. I also tested positive for donor antigen which can cause issues. Because my transplant was 33 years ago I did not have the testing that current patients go through. Thank you for caring .