Question

The extraction ratio is 0.3 and the fraction unbound in the tissue is 0.15, what is the hepatic clearance?

Answer 1

As per the question, The extraction ratio=0.3

The fraction unbound in the tissue= 0.15

So hepatic clearance=?

Hepatic clearance primarily depends on hepatic blood flow and binding to blood components is not a obstacle for extraction.

The ratio of the hepatic clearance of a drug to the hepatic blood flow is called the extraction ratio of the drug.

Hepatic drug clearance can be defined as the volume of blood perusing the liver that is cleared of the drug per unit of time.

The ratio of the hepatic clearance of a drug to the hepatic blood flow is called the extraction ratio of the drug.

Hepatic clearance CI(h)=Q[(f×C Iint)/(Q+ f×CI int)]

Q: hepatic blood flow

F: fraction of free drug ( not bount)=0.15

CI int: intrinsic capacity of the hepatocytes to metabolize a drug.