Sustained release solid oral dosage forms: single-unity or multiple-unity systems

Abstract

Sustained release solid oral dosage forms are characterized by the gradual release of the drug and maintenance of its plasmatic concentration in therapeutic levels, during a prolonged period of time. They can be designed as single-unity or multiple-unity dosage forms, using technologies such as matrix, reservoir or osmotic systems. The present work is a review on the technologies used to obtain sustained release oral dosage forms, with a special attention to the technological and biopharmaceutical benefits of multiple-unity over single-unity systems. The methods used in the evaluation of the dissolution characteristics of such systems are also approached. Examples of products available in the Brazilian market are shown with the purpose of illustrating the applicability of sustained release solid oral dosage forms, besides verifying the profile of utilization of these systems by the national industry.