Abstract
Mucoadhesion in drug delivery systems has recently gained interest among pharmaceutical scientists as a means of promoting dosage form residence time as well as improving intimacy of contact with various absorptive membranes of the biological system. Besides acting as platforms for sustained-release dosage forms, bioadhesive polymers can themselves exert some control over the rate and amount of drug release, and thus contribute to the therapeutic advantage of such systems. This paper describes some aspects of bioadhesion such as mucus layer, mucoadhesion, and theories of bioadhesion to explain the adhesion mechanism. The factors important to mucoadhesion, the methods used to study bioadhesion, and bioadhesive polymers are described. The methods that evaluate the mucoadhesive dosage forms and finally the bioadhesive drug delivery systems designed for several therapeutic purposes are presented.