How does protein binding affect lipitor's bioavailability?

How does plasma protein binding change Lipitor's blood levels?

Plasma protein binding keeps most atorvastatin bound to proteins in the blood. Only the unbound fraction can move into tissues or undergo liver metabolism. Atorvastatin binds about 98% to plasma proteins, so the free drug fraction stays very small. This pattern does not lower its oral bioavailability, however, because the liver quickly takes up the fre