Synopsis:The chemical name of FR is 8-chloro-6,11-dihydro-11 - [1 - [(5-methyl-3-pyridine) methyl] - 4-piperidyl] - 5h-benzocycloheptano [1,2-b] pyridine fumarate. It was successfully developed by uriach pharmaceutical company in Spain and was listed in Spain for the first time in 2003. It is a new generation of tricyclic antihistamines, which has the dual effects of antihistamine and antagonizing platelet activating factor (PAF). It is also the only powerful and efficient antiallergic drug on the market that has both antihistamine and PAF activity.