et was antagonized in conscious dogs by the h1-receptor antagonists pyrilamine , diphenhydramine , chlorpheniramine and promethazine ( 1-5 mg/kg i.v . ) , but not the h2-receptor antagonist cimetidine ( 2-10 mg/kg i.v . ) .
C2757048
h1-receptor antagonists
C0033405
promethazine