Drug bioavailability studies.

@article{Wagner1977DrugBS,
  title={Drug bioavailability studies.},
  author={John E Wagner},
  journal={Hospital practice},
  year={1977},
  volume={12 1},
  pages={119-27}
}
All drugs are not created equal even if the pharmacopoeia seems to suggest they are. Factors that affect bioavailability among drugs of the same type (especially oral drugs) include not only disintegration and absorption rates but also the amount of food taken before or with the dose, interactions with other drugs, the physical state of the patient, and the "first-pass effect" upon drug with high liver clearance.