The antipyretic effect of flurbiprofen.

Flurbiprofen, like its predecessor ibuprofen, possesses antipyretic properties in the endotoxin-fevered rabbit. Comparison of flurbiprofen and ibuprofen at varying dosages, reveals that flurbiprofen is at least 15 times more potent in this species. In goats, flurbiprofen is more potent than in rabbits. Flurbiprofen inhibited the pyrogenic effect of intravenously administered leucocytic pyrogen, but it did not alter the release of leucocytic pyrogen from peritoneal exudate cells in vitro. Moreover, flurbiprofen did not inhibit endotoxin-induced release of endogenous pyrogen in vivo. Incubation of leucocytic pyrogen with flurbiprofen did not alter its pyrogenic poteny. These results suggest that the antipyretic activity of flurbiprofen is due neither to interference with endogenous pyrogen synthesis and release, nor to inactivation of circulating endogenous pyrogen.