https://www.ncbi.nlm.nih.gov/pubmed/22106961

Comment; Inhibition of liver cytochrome P450 CYP3A inhibited the formation of 6β-hydroxytestosterone from testosterone and the metabolism of tacrolimus by 50%. Tacrolimus is an anti-rejection drug that inhibits T-Cell activity by increasing T-cell regulation. The rank order of inhibition of 6β-hydroxytestosterone formation from testosterone and the metabolism of tacrolimus, is ketoconazole > itraconazole > voriconazole > fluconazole. Antifungals cannot be used with impunity; consideration of interactions must be made!

Dr. Raymond Oenbrink