Mucoadhesive.

Micro-particulate systems have already shown their potential as a carrier in delivery of many therapeutic molecules. Due to this potential, such systems are now most preferred over other conventional systems of drug delivery. Micro-carriers (Microspheres) shows features like controlled release, improvement in the residence time and thus enhancing bioavailability of administered drug. Nasal microspheres are now a day’s becoming more popular for delivery of many therapeutic moieties. For building of microparticulate systems polymers from natural and synthetic origins are generally used. Drugs which are not suitable for oral administration due to high first pass effect (i:e presystemic metabolism), instability in gastrointestinal tract can be successfully delivered via nasal route. Systems like mucoadhesive microspheres provide sufficient time for drug to remain in contact with mucosal membrane so as to increase their absorption. This is the basic underlined reason suggests why most of the polar drugs have shown improvement in the bioavaibility when compared with their conventional intranasal formulations. This review mainly focuses on the basic aspects of microspheres as a potential carrier in the drug delivery.