Release Test of Indomethacin Suppository from Macrogol Bases

Abstract

Release of indomethacin from 6 kinds of commercially available macrogol suppositories (products A to F) was studied. The release profile of indomethacin from products A to E was similar. The amount released from each product during 150 min was more than 95%. However, the release of product F was considerably slow as compared with products A to E, and the release rate was 81% in 150 min. Indomethacin suppositories, prepared in different proportion of macrogols, were compared with products A to F. When the base was prepared with two macrogols, the release rate of indomethacin decreased with an increase of the content of macrogol 4000 or 6000. For the base composed of macrogol 6000 alone, indomethacin was released slowly. For macrogol suppositories studied, linear relations were found between the amount released and the square root of time. The values of lag time and release rate were obtained from each linear equation. These values were important to evaluate the release profile of drug from suppositories.