ABSTRACT
INTRODUCTION In this chapter, we will examine the major mechanisms of chemical decomposition of pharmaceuticals in the context of common functional groups. The major mechanisms of chemical decomposition of pharmaceuticals include hydrolysis/dehydration, oxidation, isomerization/epimerization, rearrangements, decarboxylation, dimerization/polymerization, and photolysis and transformation products involving reaction with excipients/salt forms. In order to develop an understanding of the chemistry of such reactions, a basic knowledge of organic chemistry is needed. Providing such a background is not the purpose of this book, and therefore the reader may fi nd it useful to consult more advanced organic chemistry textbooks and literature references. A good general organic chemistry reference is Advanced Organic Chemistry by J. March ( 1 ). Stewart and Tucker have provided excellent references for consideration of drug degradation mechanisms ( 2 ). An in-depth discussion of the various mechanisms is beyond the scope of this chapter, but some discussion is warranted.
