Formulation and Evaluation of Mucoadhesive Buccal Tablets of Pravastatin

The present study involves the formulation and evaluation of buccal tablets of Pravastatin, an antihyperlipidemic drug which has high first pass metabolism, So buccal drug delivery has been considered an alternative to the oral dosing for compound subjected to degradation in the gastrointestinal tract or to first pass metabolism. An attempt has been made to developed mucoadhesive buccal tablets comprising of drug containing mucoadhesive layers and drug free backing layer ethyl cellulose of to release the drug for extended period of time with reduction in dosing frequency, dose related side effects and improve bioavailability of drug. Tablets of Pravastatin were prepared by direct compression using mucoadhesive polymers Carbopol 943-P HPMC K4M and Sodium CMC. Buccal tablets were evaluated by different parameters such as thickness, hardness, weight uniformity, content uniformity, swelling index, surface pH,  bioadhesive strength, in vitro drug release, ex vivo drug permeation and FTIR studies. The modified in vitro assembly was used to measure the bioadhesive strength of tablets with fresh goat buccal mucosa as model tissue. In order to determine the mode of release, the data was subjected to Krosmeyer and Peppas diffusion model. All the formulations followed Fickian release mechanism. Tablet containing Carbopol 934P & Na CMC in the ratio of 1:1 had maximum in vitro drug release for 6 hrs.