ImpromidineHistamine AgonistsHistamineReceptors, Histamine H1Histamine ReleaseReceptors, Histamine H2Receptors, HistamineHistamine AntagonistsReceptors, Histamine H3Histamine H1 AntagonistsHistamine H2 AntagonistsHistamine N-MethyltransferasePyrilamineMethylhistaminesDimapritHistidine DecarboxylaseHistamine H3 AntagonistsDopamine AgonistsHistamine AgentsCimetidineChlorpheniramineMetiamideDose-Response Relationship, DrugDiphenhydramineMast Cellsp-Methoxy-N-methylphenethylamineGABA AgonistsGuinea PigsPurinergic P1 Receptor AgonistsMuscarinic AgonistsBasophilsThioureaNicotinic AgonistsAdrenergic AgonistsAdrenergic alpha-2 Receptor AgonistsSerotonin 5-HT2 Receptor AgonistsAdrenergic beta-AgonistsSerotonin 5-HT1 Receptor Agonists