Table 2.

Sites of potential interaction with colchicine

Process	Mediated by	Drugs that may interact
Absorption	CYP3A4 and P-gp in wall of small intestinea	Inhibitors or inducers of CYP3A4 and P-gp in wall of small intestine
Hepatic metabolism	CYP3A4 and P-gp in liver	Inhibitors or inducers of CYP3A4 and P-gp in liver Hepatotoxic drugs (theoretically)
Biliary excretion	P-gp in liver	Inhibitors or inducers of P-gp in liver
Renal excretion	Glomerular filtration P-gp in kidney	Nephrotoxic drugs (theoretically) Inhibitors or inducers of P-gp in kidney
Myotoxicity	Possible additive effect with myotoxic effect of colchicine	Drugs that cause myopathy

^aColchicine undergoes enterohepatic circulation, it may be exposed to CYP3A4 and P-gp more than once