ABSTRACT
This chapter addresses the pharmacokinetic techniques that are commonly used to interpret the results of animal absorption, distribution, metabolism, and excretion (ADME) studies. Since a limited number of animals are normally employed, the data should be viewed in a semiquantitative manner and caution must be exercised in extrapolating the findings to the species as a whole. The bioavailability of a compound can be estimated by comparing the blood or plasma level curves for the parent drug to those obtained from an intravenous reference dose. The rate of bioavailability is indicated by the time required to achieve peak concentration, which can be obtained directly from the drug concentrationtime curve. The data would suggest that 94% of the low oral dose and 92% of the high dose were absorbed. However, owing to the possibility of drug metabolism in the gut epithelium or by intestinal microflora, the actual amount unabsorbed could be considerably greater.
