Biopharmaceutics

Abstract

Biopharmaceutics is the field that investigates and describes everything that happens with a medicinal product and the active substance between the moment of administration, the moment it exerts its action and the moment it is eliminated from the body. Biopharmaceutics connects the physico-chemical properties of an active substance and its dosage form with its action and fate in the living organism. It encompasses pharmacokinetics, pharmacodynamics and drug delivery technology. The route of administration, the way the active substance is released from the dosage form, and the way the body handles (absorbs, distributes, metabolises and excretes) the active substance, together determine its (duration of) action, its efficacy and the occurrence of adverse effects. This chapter explains general principles of biopharmaceutics and their implications on the design of medicines. It describes the general biopharmaceutical principles that are relevant to the major routes of administration: parenteral, oromucosal, oral, rectal, dermal, nasal, pulmonary and ocular. Topics discussed include solubility and dissolution, bioavailability, partition coefficient and pH partition theory, the biopharmaceutical classification system (BCS), excipient-, food-, drug- and herb-drug interactions, first-pass effects and drug metabolism, bioequivalence and new developments in the field of advanced drug delivery systems.

Based upon the chapter ‘Biofarmacie’ by Erik Frijlink, Farida Kadir and Herman Vromans in the 2009 edition of Recepteerkunde.