Design and Evaluation of Sustained Release Bilayer Tablet of Metformin Hydrochloride with Metoprolol Tartrate

Diabetes mellitus generally accompanied with major complications like Hypertension, Cardio myopathy, Stroke, Hyperlipidemia, Ischemic cerebrovascular disease, and Peripheral vascular disease. These conditions account for most morbidity and mortality among middle-aged and older people. The drug of choice for type2 diabetes mellitus is Metformin hydrochloride and for Hypertension is Metoprolol tartarate, to reduce the prevention of cardiac problems in diabetic patients. The objective of this research work was to overcome the above complication and to establish Bilayer tablet of Metformin hydrochloride (SR) with Metoprolol tartarate (IR) as a once daily formulation. The formulations of tablets (B1- B10) were prepared by using release retarding agents like HPMC K100, Eudragit S 100 for sustained release (SR) layer and super disintegrants like Crosspovidone, Sodium starch glycolate (SSG) for immediate release (IR) layer. Both sustained and immediate release granules were evaluated for flow property. Bilayer tablets were evaluated for weight variation, hardness, thickness, swelling index and in-vitro drug release for 12 hours. All the formulations obey Zero order release kinetics and the mechanism of drug release was found to be nonfickian diffusion by fitting the data to peppas equation. The result suggest that the developed Bilayer tablet of Metformin hydrochloride (SR) with Metoprolol tartarate (IR) could perform therapeutically better and improve efficacy than conventional dosage forms, and also it trounce the severe diabetic complication especially hypertension.