AN OVERVIEW ON BILAYERED TABLET TECHNOLOGY

Bilayer tablet is new novel of tablet for the successful development of controlled release formulation along with many  features to provide a way of successful drugdelivery system. Bi-layer tablet is suitable for sequential release of two drugs incombination, separate two incompatible substances and also for sustained release tablet in which one Layer is immediaterelease as initial dose and second layer is maintenance dose. So use ofbi-layer tablets is a very differentaspectfor anti-hypertensive, diabetic, anti-inflammatory and analgesic drugs where combination therapy is often used.  Bi-layer tablets have been developed to achieve modified release of drug. Bilayer tabletis improved beneficial technology to overcome the shortcoming of the single layered tablet. In the case of bilayered tablets drug release can be rendered almost unidirectional if the drug can be incorporated in the upper non adhesive layer its delivery occurs into the whole oral cavity.To reduce capital investment, quite often existing but modified tablet presses are used to develop and produce such tablets. The present article explains why the production and development of quality bi-layer tablets needs to be carried out on purpose-built tablet presses to overcome common bi-layer problems, such as hardness, insufficient, layer-separation, inaccurate individual layer weight control, reduced yield, cross-contamination between the layers, etc. Using a modified tablet press may therefore not be your best approach to producing a quality bi-layer tablet under GMP-conditions. Keywords:Approaches, Bilayer tablets, OROS push pull technology, DUROS technology,immediate release, GMP requirements for bilayer tablet