Mucoadhesive hydrogels gastrointestinal route

Noninvasive drug delivery may require the administration of the drug delivery system (DDS) at an epithelium as a suitable site of absorption of the active compormd. Such regions are usually called mucosae. In the human body several mucosal sites can be identified, the one mostly used for administration and absorption of therapeutics being the gastrointestinal route. In order to increase the residence time at these absorption sites, a so-called mucoadhesive delivery system has to be used. Generally, these systems consist of one or more types of hydrogels. 

Specific type of mucoadhesive compounds, like lectins, have been evaluated to solve the difficulties presented by conventional mucoadhesive hydrogel systems, for instance in the gastrointestinal route. Since these compoimds do not belong to the class of hydrogels, they are not extensively discussed here. 

During the last decade research was particularly focused on the delivery of mucoadhesive dosage forms in the gastrointestinal tract, which is the most favorable route of delivery with regard to patient compliance and ease of application. For this reason microparticulate formulations, consisting of mucoadhesive hydrogels. 

---