The powder characteristics of the direct compression excipients Cellactose, Tablettose, spray dried lactose (SDL) and Avicel PH101 were compared.  These excipients and a mixt. of Avicel:SDL (1:3) were used for the prepn. of glibenclamide tablets.  The tablet characteristics, including the phys. properties, av. drug content, as well as the dissoln. rate were evaluated before and after the tablets were subjected to storage under two accelerated conditions: 40°C​/30​% relative humidity (RH) for 16 wk and 40°C​/80​% RH for 12 wk.  The results showed that SDL has the best flow properties followed by Tablettose, Cellactose and Avicel.  With regard to tablet characteristics, Tablettose produced tablets with the least wt. variations before and after storage at both low and high relative humidity, while a mixt. of Avicel:SDL (1:3) produced tablets that gave the highest values.  Cellactose was the best vehicle in preserving the tablet size and glibenclamide content during storage.  On the other hand, the least changes obsd. in the dissoln. profiles of glibenclamide tablets due to storage was found for tablets made of Avicel followed by these of Cellactose and a mixt. of Avicel:SDL (1:3)​.