In CHO-K1/hERG cells,SUN-1334H causes potent inhibition of histamine induced contractions of isolated guinea-pig ileum(IC50 : 0.198 μM)[2].

In beagle dogs and ovalbumin-induced rhinitis in guinea pigs, SUN-1334H potently inhibits histamine-induced bronchospasm over 24 hours following oral administration and completely suppresses histamine-induced skin wheal [1]. SUN-1334H shows potent reduction of passive and active cutaneous anaphylactic reactions in skin allergy models. In central nervous system side effects models, SUN-1334H, desloratadine and fexofenadine are devoid of any significant effects[2].