ABSTRACT
Relevant aspects of the composition and performance of modified release coatings are considered in this chapter. Initially, the basic characteristics of multiparticulate systems are described and comparisons are made with the performance of whole tablets intended for modified release. The properties and effects of the polymers and plasticizers which are used in modified release coatings are illustrated with examples from the literature. This further develops the basic treatment of these materials provided in Chapter 2. Additional ingredients peculiar to modified release coatings, such as pore-forming agents, are also described. A section on the structure and function of modified release films and the mechanism of drug release from the coated particle or tablet is also included.
