Since Pasteur in 1846, scientists have been aware that many drugs are photoreactive, but until recently research in this area had been somewhat limited. However, since the introduction of acutely sensitive analytical methods, the realisation of the need to identify the photochemical properties of a potential drug as early in its development as possible and the increased attention to the phototoxic effect of drugs, more details are becoming available. Drugs: Photochemistry and Photostability presents the basic elements of the science, and serves as an excellent introduction to this emerging field of photochemistry. Detailed experimental conditions for photostability studies are given, along with a discussion of the recently implemented ICH Guidelines for drug photostability. With contributions from international experts in the field and including a comprehensive literature review, this book provides all the up-to-date information needed by researchers in many fields, especially medicinal and pharmaceutical chemistry.