All of the following statements regarding bioavailability of a drug are true except:
- Bioavailability is the fraction of administered drug that reaches systemic circulation in unchanged form. So it depends on Absorption and first pass metabolism.
- In case of oral bioavailability, it may be low due to decreased absorption or high first pass metabolism.
It is a fraction of administered drug that reaches the systemic circulation in unchanged form
Bioavailability of an orally administered drug can be calculated by comparing the Area Under Curve after oral and intravenous administration
Low oral availability always and necessarily means poor absorption
Bioavailability can be determined from plasma concentration or urinary excretion data.