Bioadhesive formulations have a wide scope of application for both systemic and local effects of the drug. The oral transmucosal drug delivery bypasses liver and avoids pre-systemic elimination. The strategies to overcome such obstacles include the employment of new materials that, possibly, combine mucoadhesive and penetration enhancer properties and the design of novel drug delivery systems which, besides improving patient compliance, favor a more intimate contact of the drug with the absorption mucosa. Cellulose derivatives like HPMC is having good mucoadhesive property however its...