Thermally gelling poloxamine Synperonic T908 solution as a vehicle for rectal drug delivery

Thermally reversible gels of the block copolymer, Synperonic T908, have been evaluated as vehicles for the rectal administration of indomethacin. Prolonged plasma levels of indomethacin following rectal administration in such gels was observed with the 40% w/w Synperonic T908 gels when compared with commercial suppositories. The release rate decreased with an increase in gel concentration over the range 30% to 40% w/w. Histological observation showed no damage to the rectal mucosal membrane in animals at 6 h after the administration of a 40% w/w gel.