Adverse effects of FK 506 overdosage after liver transplantation.

Abstract

FK 506 and cyclosporine (CyA) are not chemically related and have different cytosolic binding sites.1,2 However, it was noted almost immediately after FK 506 was introduced clinically that its toxicity profile was similar to CyA.3–5 The principal side effects of nephrotoxicity,3–6 diabetogenicity,7,8 and neurotoxicity9,10 have been reported individually. However, we will present here the full range of these and other adverse reactions together in the first 370 consecutive liver recipients who were entered into the Pittsburgh FK 506 study during 1989 and 1990. This case accrual was during a learning curve in which the daily induction doses were two or three times greater than those presently recommended. Consequently, a unique and unintended opportunity existed for overdose toxicology studies.