The aim of the present work focused on the theoretical and practical aspects of the dissolution studies of the modified release pharmaceutical dosage forms. This paper was divided in three parts: the first refers to the classification, therapeutic interest and release of the drug; the second part presents the theory of the dissolution process, the models of drug release, dissolution systems and their validation, specifications and acceptance criteria for the dissolution studies and the factors conditioning the dissolution, release and absorption of the drug; the third part discusses the conditions in which the dissolution studies are performed and the physiological parameters making reference to the dissolution media, to the composition of the gastrointestinal tract lumen and to the hydrodynamic models.
In vitro dissolution; Modified release; Dissolution models; Absorption; Hydrodynamics
