Mucoadhesive polymers for delivery of drugs to the oral cavity.

Local therapy of the oral cavity is used to treat conditions such as gingivitis, oral candidosis, oral lesions, dental caries, xerostoma and oral carcinomas. Delivery systems used include mouthwashes, aerosol sprays, chewing gums, bioadhesive tablets, films, gels and pastes. There are three major problems associated with drug therapy within the oral cavity: rapid elimination of drugs due to the flushing action of saliva or the ingestion of food, the non-uniform distribution of drugs within saliva on release from a solid or semisolid delivery system and patient compliance in terms of taste. Prolonged contact time of a drug with body tissue can significantly improve the clinical performance of many agents used for treating oral disorders. These improvements range from better treatment of local pathologies to improved drug bioavailability and controlled release to enhanced patient compliance. There are abundant examples in the literature over the past 15 years of these improvements using bioadhesive polymers. This manuscript summarizes the innovations pertaining to formulation and treatments as described in recent patents.