First-pass metabolism of cyclosporin by the gut.
Cyclosporin is thought to be exclusively metabolised in the liver. We instilled cyclosporin into the small bowel of 2 patients during the anhepatic phase of liver transplantation; cyclosporin metabolites were readily detected in portal venous blood. Our findings indicate that the small intestine is a major site of cyclosporin breakdown: such intestinal metabolism might help to explain the poor oral bioavailability and drug interactions of cyclosporin.
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.
J C
JC
Kolars
W M
WM
Awni
R M
RM
Merion
P B
PB
Watkins
D001682:Biological Availability; D016572:Cyclosporine / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics; D006801:Humans; D007408:Intestinal Absorption / Q000187:drug effects; D007421:Intestine, Small / Q000378:metabolism*; D016031:Liver Transplantation; D011169:Portal Vein
D016572:Cyclosporine