DISSOLUTION ENHANCEMENT OF CARVEDILOL BY USING SURFACTANT AS A COATING MATERIAL

Carvedilol is a poorly water-soluble oral antihypertensive agent, with problems of variable bioavailability and bio-in equivalence. This work was investigated to develop the carvedilol tablets, allowing fast, reproducible and complete drug dissolution, by using surfactant. The tablets were prepared by wet granulation technique. The prepared tablets were evaluated for thickness, uniformity of weight, hardness, friability, in-vitro disintegration time and in-vitro drug release. The tablets apart from fulfilling all official and other specifications, the Carvedilol dissolution profile from the newly developed tablets was clearly better than those batches without surfactants in the coating. The stability studies conducted as per ICH guidelines at 40°±2° and 75%±5% RH showed insignificant loss in drug content and on physical evaluations at the end of three months. So many techniques are available for the solubility enhancement such as micronization, spray drying, and complex formation. Some drugs such as carvedilol, zolpidem tartarate may show change in polymorphism by using above techniques. The purpose of the research was to increase the solubility of carvedilol by adding the surfactants in coating without changing its polymorph so as to develop an immediate release formulation. The study shows that the use of 3 % surfactant increases the dissolution rate up to 12 % in first 20 minutes in pH 6.8 Phosphate buffer, USP II, 50 rpm. Thus by incorporating the surfactants like tween 80, we can enhance the solubility of low solubility drugs.