ABSTRACT
The choice of the best excipients for the formulation of remedies is of vital importance in ensuring the stability and efficacy of the resulting preparations (1). As formulation scientists, it is imperative that the products we develop have acceptable chemical and physical stability during the period of their distribution and storage. It is not uncommon that an active pharmaceutical ingredient (API) will be stable as bulk drug but unstable when blended with the excipients required for formulation of dosage forms. Understanding the reactivity of the API in the solid state when mixed with excipients is critical to commercial formulation development. Because the gathering of real-time stability and compatibility data is impractical in the early stages of development, we must rely on stress testing and accelerated stability methods for predicting ambient condition interactions and rates of degradation. Often such studies will require innovative approaches to minimize the amount of compound used and to maximize the detection of small quantities of degradation products. This chapter will focus on summarizing approaches to designing, measuring, and interpreting solid-state excipient compatibility data.
