Evaluation of Photostability of Medicines and Development of the Photostabilization of the Photosensitive Medicines

Abstract

Photo-exposure has a crucial effect on both the quality and quantity of photosensitive pharmaceuticals due to the decrease of their contents or the expression of adverse effects derived from generated photoproducts. The photostability test guidelines (ICH-Q1B, Photostability testing of new drug substances and products) have been established for the photostability evaluation in the new drug application, and obtained results from these tests are required for the elucidation of the final packaging and the dosage form. However, there is no information in the interview form about the photostability of medicines that are taken out from a press through package (PTP) sheet and their dosage forms are changed for the purpose of the improvement of medication compliance of patients. It is an important issue to clarify the photostability of medicines that are crushed or suspended and determine the potential photoproducts for safe use. Herein, in this review, results of the evaluation of the photodegradability of photosensitive active pharmaceutical ingredients (APIs) and their formulations, the determination of several photoproducts generated by ultraviolet-light (UV) irradiation and the development of photostabilization strategy for them based on the addition of several photostabilizers are summarized.