<Interesting! Bile is being produced, blocked, and absorbed into the
<blood.  What effect would drugs have on the liver though?  I would
have
<thought drugs would decrease bile production, but can they block it
<also?

<Bob S.

With regards to Zetia,

"The liver can synthesize cholesterol, take up cholesterol from the
blood from circulating lipoproteins, or take up cholesterol absorbed by
the small intestine. Intestinal cholesterol is derived primarily from
cholesterol secreted in the bile and from dietary cholesterol.
Ezetimibe has a mechanism of action that differs from those of other
classes of cholesterol-reducing compounds (HMG-CoA reductase
inhibitors, bile acid sequestrants [resins], fibric acid derivatives,
and plant stanols).

Ezetimibe does not inhibit cholesterol synthesis in the liver, or
increase bile acid excretion. Instead, ezetimibe localizes and appears
to act at the brush border of the small intestine and inhibits the
absorption of cholesterol, leading to a decrease in the delivery of
intestinal cholesterol to the liver. This causes a reduction of hepatic
cholesterol stores and an increase in clearance of cholesterol from the
blood; this distinct mechanism is complementary to that of HMG-CoA
reductase inhibitors (see CLINICAL STUDIES)."

Drugs in general may be directly hepatotoxic as most are because the
liver is the organ that gets rid of drugs. When the organ is damaged
then bile builds up in the liver as the normal channels of excretion
are damaged and is washed out via the blood which is counter productive
as the toxins must be normally excreted via the bile. Drugs in general
may interfere with function and physiology at the organ level as is the
case with the liver and gallbladder or pancrease. The gallbladder
squirts the bile via smooth muscle action. Gallbladder atonic paralysis
may happen with certain disease or conditions.

Bile is a mixture of fluid with waste that is normally excreted through
the stool and has a biological role in fat absorption.
Lack of bile may result in a decrease of fat absorption with highly
fatty meals and cause malabsorption of certain fats and fat soluable
vitamins. The stool comes out loose and really smelly. Hard to flush
down the toilet as it is lighter than normal.

Is there concern about this yes as you can see from such studies that
specifically look at that.

"ZETIA had no clinically meaningful effect on the plasma concentrations
of the fat-soluble vitamins A, D, and E (in a study of 113 patients),
and did not impair adrenocortical steroid hormone production (in a
study of 118 patients). The cholesterol content of the liver is derived
predominantly from three sources. "

http://www.healthcentral.com/cholesterol/find-drug-679-133.html