Development of Novel Co-Processed Excipients for the Design and Evaluation of Directly Compressible Tablets of Rizatriptan Benzoate

A novel co-processed excipient containing different ratios of lactose: maize starch were prepared and tested their suitability for development of direct compressible tablets of Rizatriptan benzoate. Rizatriptan is a 5-HT1 agonist, used in the treatment of migraine headaches, The Rizatriptan dose is 10mg, so it is suitable for direct compression but it has poor flow, poor disintegration, and poor compressibility. To overcome these problems, the tablets were formulated by using co-processing excipients (lactose and maize starch). Co-processed excipients with α-lactose monohydrate and Maize starch in different ratios (100:0, 0:100, 50:50, 60:40, 70:30, 80:20, and 90:10) were fabricated by wet granulation technique and its influence on blend fluidity, friability of the tablet and dissolution characteristics of Rizatriptan benzoate from direct compressible tablets were studied. The flow properties of the blends were determined by Carr's index and Hausner's ratio. Higher proportion of lactose and maize starch individually imparted low flowability, low disintegration properties, and failed to meet the friability. Optimized co-processed formulation containing lactose and maize starch in the ratio of 90:10 was found to be more acceptable to formulate Rizatriptan benzoate tablets.