Characterization and Performance of a New Direct Compression Excipient for Chewable Tablets: Xylitab®

Abstract

Xylitab® is a commercially available direct compression form of xylitol. Two grades of this material, Xylitab 200 and Xylitab 100, were evaluated for compaction, flow, lubrication requirements, and dilution potential. As expected, the products required lubrication for tableting, and a level of 0.5% magnesium stearate and 0.5% stearic acid was found to give the best performance. Compaction profiles were generated using both an instrumented single-punch press and a rotary tablet press. Tablets up to hardness values of 20 Kp were obtained on the single-punch press; the maximum hardness values on the rotary press was 11 Kp. Flow behavior on the tablet presses was excellent as shown by tablet weight uniformity data with less than 1% RSD values. Further evaluation by Heckel analysis showed that both products exhibit brittle and viscoelastic behavior, and undergo elastic recovery primarily in the die. To test dilution potential, powdered acetaminophen was selected as a severe test material. Under these conditions, 20% drug still produced an acceptable tablet, but hardness values were reduced as expected. With a directly compressible grade of acetaminophen, a complete chewable formulation was successfully produced using Xylitab 200 as the main direct compression excipient and sweetening agent. Xylitab exhibits acceptable properties as a direct compression chewable tablet excipient and warrants further study.