V. Hima Bindu et al/JGTPS/Volume 4, Issue 2, April – June 2013 1077 V. Hima Bindu Email- veminani@gmail.com Address for correspondence AN OVERVIEW ON BILAYERED TABLET TECHNOLOGY INTRODUCTION 1, 2 In the last decade, interest in developing a combination of two or more Active Pharmaceutical Ingredients (API) in a single dosage form (bi-layer tablet) has increased in the pharmaceutical industry, promoting patient convenience and compliance. Bi-layer tablets can be a primary option to avoid chemical incompatibilities between APIS by physical separation, and to enable the development of different drug release profiles (immediate release with extended release). NEED OF BILAYER TABLETS 3, 4, 5 1. For the administration of fixed dose combinations of different APIs, prolong the drug product life cycle, buccal/mucoadhesive delivery systems; fabricate novel drug delivery systems such as chewing device and floating tablets for gastro-retentive drug delivery. 2. Controlling the delivery rate of either single or two different active pharmaceutical ingredient(s) 3. To modify the total surface area available for API layer either by sandwiching with one or two in active layers in order to achieve swellable/erodible barriers for modified release. 4. To separate incompatible Active pharmaceutical ingredient (APIs) from each other, to control the release of API from one layer by utilizing the functional property of the other layer (such as, osmotic property). ADVANTAGES OF THE BILAYER TABLET DOSAGE FORM 1. Bi-layer execution with optional single-layer conversion kit. 2. Cost is lower compared to all other oral dosage form. Research Article Bi-layer tablet is a new era for successful development of controlled release formulation along with various features to provide successful drug delivery. Bi-layer tablets can be primary option to avoid chemical incompatibilities between APIs by physical separation and to enable the development of different drug release profiles. Bi-layer tablet is suitable for sequential release of two drugs in combination and also for sustained release of tablet in which one layer is for immediate release as loading dose and second layer is maintenance dose. So use of bi-layer tablets is a very different aspect for anti-hypertensive, diabetic, anti-inflammatory and analgesic drugs where combination therapy is often used. Several pharmaceutical companies are currently developing bi-layer tablets, for a variety of reasons: patent extension, therapeutic, marketing to name a few. General tablet manufacturing principles remain the same, there is much more to consider because making multi-layer tablets involves multiple often incompatible products, additional equipment and many formulation and operation challenges. The present article provides an introduction to bi-layer tablet technology, challenges in bi-layer tablet manufacturing, various tablet presses used, quality and GMP requirements for their production various techniques used for bi-layer tabletting and recent developments in the field of bi-layer technology. Keywords: Bi-layer tablet, API (active pharmaceutical ingredient), incompatibilities. ABSTRACT C. Gopinath, V. Hima Bindu*, M. Nischala Department of Pharmaceutical Technology, Annamacharya College of Pharmacy, Rajampet, 516126, (A.P) INDIA. Journal of Global Trends in Pharmaceutical Sciences Available online at www.JGTPS.com ISSN: 2230-7346 Journal of Global Trends in Pharmaceutical Sciences Volume 4, Issue 2, pp -1077-1085, April- June 2013