Liver Dysfunction On Pharmacokinetics Flashcards
Where does drug metabolism and elimination occur in the liver
In the heptoacytes using CytochromeP450
Where are the blood supplies of the liver from
Hepatic Artery
Portal vein
What has more metabolic enzymes liver or intestinal epithelium
Liver
What phrase does this statement belong to
- unidirectional ATP-dependant export pumps belonging to ATP-binding cassette
Biliary excretion
Hepatic extraction ratio
Fraction of drug entering liver in blood which is removed during one pass of blood through liver
What does the hepatic extraction ration depend on
Blood flow
Percent of drug bound to blood
Intrinsic clearance
What Eh does high hepatic extraction ratio have
> 0.7
What Eh does a low hepatic extraction rate have
<0.3
What does the intermediate hepatic extraction ratio have as its Eh
0.3
High hepatic extraction ratio -
Does blood flow increase and why
Increases amount of drug present to and eliminated by the organ
Hepatic clearance
Volume of blood which is removed completely by liver/ unit time
In low hepatic extraction ratio what does the venous drug concentration equal
Arterial concentration
Name the 2 steps which occur after oral dose
Absorption in intestinal epithelial cells
Portal circulation
What two things is oral clearance determined by
Protein plasma binding
Intrinsic clearance
What does systematic clearance assume
Drugs are eliminated by liver
