Assessment of test methods evaluating mucoadhesive polymers and dosage forms: an overview

Oral mucoadhesive preparations have gained increasing importance in the last decades, by reason of numerous advantages like easy application, discrete handling and no swallowing of the drug product. Pharmacopoeial methods to study mucoadhesion are not available so far, despite the new monograph for oromucosal preparations is valid since the European Pharmacopoeia 7.4 (2012) including a chapter on mucoadhesive preparations. Several mucoadhesion test methods are reviewed concerning the applicability for various polymers, different drug dosage forms and comparability of experimental set-ups. Different test methods and experimental set-ups lead to huge differences regarding the results.