bioadhesion

The present research work describes the  improvement of  bioavailability of Isradipine through buccal delivery. Isradipine buccal tablets were prepared with β cyclodextrin which improved the photostability of the drug. Buccal formulations were evaluated for in vitro release, moisture absorption, mechanical properties, and bioadhesion, and optimized formulation was subjected for bioavailability studies in healthy human volunteers and compared with marketed tablet. The pharmacokinetic parameters Cmax, tmax and AUCo-t of test formulation were calculated and compared with the reference i.e., marketed product. It was observed from the study that the drug release from the test formulation could be sustained and it was concluded that the test formulation was able to sustain the drug release as compared to reference marketed product with 1.672 fold increase in extent of absorption i.e., AUC0-t.

Floating drug delivery system is suitable for NVP as the absorption and solubility of NVP is high at pH

  Promethazine Hydrochloride (PMZ), a low bioavailabe drug, used for the management of emesis. The purpose of the present investigation was to develop buccoadhesive tablets for PMZ and to evaluate for their physicochemical, in vitro, ex vivo and in vivo parameters. Ex vivo drug permeation through porcine buccal membrane from the drug solution was conducted to know the permeation characteristics of the PMZ. The controlled-release PMZ tablets were produced by direct compression method using Sodium CMC and Carbopol 934P as mucoadhesive polymers and evaluated for in vitro drug release, in vitro bioadhesion, in vivo residence time, swelling and erosion studies, surface pH, ex vivo drug permeation through porcine buccal membrane from the optimized buccal tablet (F10) and stability studies. Formulation F10 showed maximum drug release (96.3 %) in 6 h, with the Higuchi model release profile and permeated 49.8 % of the drug with flux 1.45 mg h–1cm–2 through porcine buccal membrane. The optimized formulation showed peak detachment force (1.64 N), work of adhesion (0.36 mJ), in vivo residence time (287 min), swelling index (204%), erosion (53.1%) and surface pH (6.92). In vivo mucoadhesive behaviour of the optimized formulations was studied in healthy human volunteers and subjective parameters were evaluated. The stability of the optimized formulation was studied and no significant changes were detected in drug content and in vitro release after 6 months. PMZ mucoadhesive tablets for buccal delivery could be prepared with required permeation, bioadhesive and in vivo residence properties.