[Content uniformity of warfarin-containing mixtures and tablets]

This experimental study describes the method of direct compression of powder mixtures composed of warfarinum sodium salt. Warfarinum is a drug with a narrow therapeutics index. The aim of this study is to find a suitable composition and a process of preparing tablets with the best uniformity. The content uniformity is very important for the safety of the therapy. This study links up with the already published article including the results of content uniformity of mixtures and tablets prepared by direct compression. These mixtures contain fillers with different density and distribution size of the particles (excipients with digger particles were used in this experiment). The study is focused on the influence of magnesium stearate, which was added at the beginning of the homogenization or after the mixing of the other components. In addition to content uniformity and physical characteristics of the tablets, the study also evaluated the uniformity and physical characteristics of the mixtures. In this experimental study it has been found out that content uniformity is influenced by the total time of homogenization and the addition of magnesium stearate and much less by the distribution size of the particles of excipients in the mixtures. The appropriate selection of process parameters is important for obtaining tablets respecting the strict criterion of Bergum distribution. This distribution is a part of the GMP by the evaluation of the content uniformity in the U.S.