Cholinergic AntagonistsReceptors, Histamine H3Receptors, Histamine H1HistamineReceptors, Histamine H2Histamine H1 AntagonistsScopolamine HydrobromideHistamine H2 AntagonistsHistamine AgonistsHistamine AntagonistsReceptors, HistamineMuscarinic AntagonistsHistamine H3 AntagonistsParasympathomimeticsAtropineMecamylamineCholinergic AgonistsParasympatholyticsHistamine ReleaseMethylhistaminesQuinuclidinyl BenzilateReceptors, CholinergicCarbacholChlorpheniramineDimapritCimetidineAcetylcholineReceptors, MuscarinicDose-Response Relationship, DrugMetiamideThioureaPiperidinesImpromidineDiphenhydramineFamotidineGuinea PigsAction PotentialsPyrilamineHormone AntagonistsRanitidineHistamine N-MethyltransferaseHistamine AgentsBurimamideHistamine H1 Antagonists, Non-SedatingDopamine AntagonistsNeurokinin-1 Receptor AntagonistsExcitatory Amino Acid AntagonistsHistidine DecarboxylaseNarcotic AntagonistsDoxepinRadioligand AssayInterleukin 1 Receptor Antagonist ProteinIsothiuroniumRats, Sprague-DawleyRats, WistarGABA AntagonistsReceptors, G-Protein-CoupledPurinergic P1 Receptor AntagonistsTripelennamineGastric Acidp-Methoxy-N-methylphenethylamineNicotinic AntagonistsTerfenadineAdenosine A2 Receptor AntagonistsAdrenergic alpha-1 Receptor AntagonistsBinding, CompetitiveTriprolidinePurinergic P2 Receptor AntagonistsMast CellsKetotifenSerotonin 5-HT3 Receptor AntagonistsSerotonin 5-HT2 Receptor AntagonistsLeukotriene AntagonistsImidazolesPyridinesTime FactorsMuscle, SmoothPruritusIndolesDrug InteractionsAdenosine A1 Receptor AntagonistsBenzazepinesDibenzoxepinsPiperazinesAngiotensin Receptor AntagonistsCells, CulturedMuscle ContractionGuanidinesBetahistineSerotoninCetirizineAdrenergic alpha-AntagonistsReceptors, SerotoninAdrenergic alpha-2 Receptor AntagonistsAdrenergic AntagonistsGastric MucosaGABA-A Receptor AntagonistsCyclic AMPSubstance PCyproheptadine