Biopharmaceuticals oral drug absorption

The last section of this chapter is devoted to the regulatory aspects of oral drug absorption and in particular to the biopharmaceutics classification system and the relevant FDA guideline. At the very end of the chapter, we mention the difference between randomness and chaotic behavior as sources of the variability encountered in bioavailability and bioequivalence studies. 

Next to permeability, aqueous solubility is the most important biopharmaceutical property associated with oral drug absorption. These two properties have established the basis for a biopharmaceutical classification system (BCS) and have become the subject of an FDA guidance entitled Waiver of In Vivo Bioavailability and Bioequivalence Studies for Immediate-Release Solid Oral Dosage Forms Based on a... 

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