Buccal tablets

The present study involves the formulation and evaluation of buccal tablets of venlafaxine hydrochloride, an antidepressant drug belongs to class SNRI(serotonin-nonepinephrine reuptake inhibitor)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 muccoadhesive 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 bioavaibility of drug. Tablets of Venlafaxine Hydrochloride were prepared by direct compression using muccoadhesive polymers Carbopol 934-P and HPMC K4M.Buccal tablets were evaluated by different parameters such as thickness, hardness, weight uniformity, content uniformity, swelling index, surface pH, ex vivo 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 and HPMC K4M in the ratio of 1:1(25%) had maximum in vitro drug release for 8 hrs.

  Mucoadhesive delivery systems were proven to be suitable for the purpose of reduction of transit time of the dosage form through the gastro-intestinal tract, and increasing bioavailability of drug. Buccal tablets of Carvedilol were prepared by direct compression method for using various compositions of combination of Starch: C934 and Starch: HPMCK15M in various ratios. The tablets were evaluated for their characteristics properties, mucoadhesion and in vitro-in-vivo study. All the physicochemical properties were acceptable within the limit. Formulation containing starch and Carbopol 934(E4) showed better bioavailability as compared to tablet containing  Starch and HPMCK15 (F5) and The bioadhesive strength of the formulations containing polymers were in the order of E4> F5. Stability studies were carried out as per ICH guidelines and formulations were found to be Stable.