This chapter provides an overview of the main features that need to be
assessed with respect to the general pharmacology (pharmacokinetics, PK;
pharmacodynamics, PD) of all molecules, including natural compounds. Here, the
attention has been focused on bioavailability, the volume of distribution, and clearance
to describe the physiological processes of absorption/distribution and elimination of
drugs from the body. It is worth pointing out that PD studies always require an in vitro
preliminary approach, not issued here, that needs to be assessed and confirmed in vivo.
Indeed, PD studies aim to the individuation of specific molecular targets, responsible
for an observed pharmacological effect. Thus, the use of animal models as a complex
approach does not allow to dissect the molecular mechanisms of natural compounds
but can confirm their efficacy in vivo. Therefore, specific PD approaches to determine a
specific action by a compound are addressed in the relevant chapters within this book.
Keywords: Pharmacokinetics, Bioavailability, Distribution, Elimination, Half-life.
