Question

What is the mechanism of action of Ezetimibe (Zetia)?

1) Inhibitor of NPC1L1
2) Inhibitor of HMG-CoA reductase
3) Inhibitor of ACE
4) Inhibitor of PDE5

Answer 1

Ezetimibe (Zetia) works as an inhibitor of NPC1L1, a protein essential for cholesterol absorption in the intestine, thus reducing plasma cholesterol levels, unlike statins that inhibit HMG-CoA reductase to reduce cholesterol synthesis in the liver.

Step-by-step explanation:

The mechanism of action of Ezetimibe (Zetia) is as an inhibitor of NPC1L1. NPC1L1, or Niemann-Pick C1-Like 1, is a protein critical for the absorption of cholesterol in the intestine. By inhibiting this protein, Ezetimibe effectively reduces the amount of cholesterol absorbed from the diet, thereby lowering plasma cholesterol levels.

This is different from the mechanism of action of statins, which are inhibitors of HMG-CoA reductase, an enzyme responsible for cholesterol synthesis in the liver. While statins also lower cholesterol, their primary action is to inhibit this liver enzyme, reducing the body's internal cholesterol production.