Formulation and evaluation of mucoadhesive buccal tablets of solifenacin

Abstract

Drug delivery via buccal route, using bioadhesive dosage forms offers such a novel route of drug administration. Buccal
delivery involves administration of desired drug through the buccal mucosal membrane lining of oral cavity. Extensive
first-pass metabolism and drug degradation in the harsh gastrointestinal environment can be circumvented by
administering the drug via buccal route. The mucosal lining of oral cavity offers some distinct advantages. It is richly
vascularized and more accessible for the administration and removal of a dosage form. Additionally, buccal drug delivery
has high patient acceptability compared to other non-oral routes of drug administration. In the present study, an attempt
was made to design and evaluate mucoadhesive buccal tablets of solifenacin. Different formulations of solifenacin having
polymers at different concentrations were prepared by direct compression method. Drug and polymer interactions were
investigated by Fourier Transform Infrared (FTIR) and no interactions were detected with the used polymers. solifenacin
pure drug was evaluated for preformulation parameters. Among all formulations F2 and F8 were optimized with drug
release 98.6% and 99.6% respectively. But mucoadhesion time for F8 was less than F2 (<8hrs).hence F2 was considered
as best formulation. Among nine formulations, formulation F2 containing HPMC KM4 (10%) exhibits in-vitro drug
release of 98.6% in 8 hrs. All the formulations were subjected to post compression parameters and showed uniformity
within limits. The optimized mucoadhesive buccal tablets were evaluated for weight variation, hardness, thickness,
friability and drug content and were within specified limits. F2 was optimized based on sustained drug release at 98.6% in
8 hrs. The optimized buccoadhesive formulation followed zero-order kinetics and non-fickian release mechanism.
Stability studies as per ICH guidelines showed that there were no significant changes in the drug content.