The purpose of this study was formulation and in vitro evaluation of floating-bioadhesive tablets to lengthen the stay
of glipizide in its absorption area. Effervescent tablets were made using chitosan (CH), hydroxypropyl
methylcellulose (HPMC), carbopolP934 (CP), polymethacrylic acid (PMA), citric acid, and sodium bicarbonate.
Tablets with 5% effervescent base had longer lag time than 10%. The type of polymer had no significant effect on
the floating lag time. All tablets floated atop the medium for 23-24 hr. Increasing carbopolP934 caused higher
bioadhesion than chitosan (p < 0.05). All formulations showed a Higuchi, non-Fickian release mechanism. Tablets
with 10% effervescent base, 80% CH/20% HPMC, or 80% CP/20% PMA seemed desirable.
