Design and Development of a Self Correcting Monolithic Gastroretentive Tablet of Baclofen

Rishad R Jivani

doi:10.3797/scipharm.0905-11

Abstract

The present investigation describes the design and development of selfcorrecting monolithic Gastroretentive system of baclofen. Tablets were prepared by direct compression method. Optimization was carried out using simplex lattice design. Drug released at 2h, 4h, 8h, and floating lag time were considered as response variables related to percentages of diluent (MCC), Polyethylene oxide (PEO) and sodium bicarbonate. Tablets were evaluated for in-vitro buoyancy, in-vitro drug release, swelling index and ex-vivo bioadhesion studies. The similarity factor (f2) was used as a base to compare dissolution profiles. Drug release data was fitted into different kinetic models. The floating lag time and floating time were found to be 2min and 12h respectively. Increasing trend in bioadhesive strength was observed with an increase in the amount of PEO. The experimental values of Q2, Q4 and Q8 for check point batch were found to be 30.8%, 44.1% and 69.9% respectively. Similarity factor (f2) for check point batch was 78.08. Kinetics of drug release from tablet followed Korsmeyer–Peppas model by anamolous non-fickian diffusion. It was concluded that gastroretentive tablet of baclofen can be prepared via floating and bioadhesion mechanism to increase residence time of drug in stomach and there by increases absorption.

Highlights

Each batch contains 20mg of baclofen, 2% talc, and 1% of magnesium stearate, total weight of tablet was made to 250 mg
The methodology adopted for preparation of Gastroretentive tablet was very simple and cost effective
It was observed that for the development of controlled-release dosage form of baclofen, polymer like Polyethylene oxide (PEO) which imparts hydrophilic environment leads to more uniform drug release

Summary

Introduction

Baclofen is difficult to formulate in to sustained release products because on arrival to colon (or even before) its absorption is low or non existent in present investigation efforts have been made to increase the residence of baclofen at or above the absorption window by preparing Gastroretentive tablet for gastric retention considering fact that it is stable at gastric condition [21], applying a simplex lattice design for the optimization. The Q2, Q4, and Q8 values for all seven batches showed a wide variation i.e. the response ranged from a minimum of 9.3% to 37.1%, 20.1% to 49.9% and 44.9% to 98.8% respectively.The data clearly indicate that the Q2, Q4, and Q8 is strongly dependent on the independent factors selected in the study.

Results

Conclusion