Roles of histamine and its receptors in allergic and inflammatory bowel diseases

Table 2 Antagonists of histamine receptors.

Receptor subtype	Antagonists
H1	First-generation
	Azatadine, clemastine, chlorpheniramine
	(chlorphenamine maleate), diphenhydramine,
	dexchlorpheniramine, hydroxyzine, mepyramine (pyrilamine), promethazine, terfenadine (teldane),
	triprolidine[35-37]
	Second-generation
	Acrivastine[37,38], astemizole (hismanal)[38],
	azelastine[38], cetirizine (virilx, zirtek, zyrtec)[39-41],
	chlorpheniramine[42,43], desloratadine[44,45], ebastine[37,44],
	emedastine[37], epinastine[41,46], homochlorcyclizine[47],
	ketotifen[41,48] levocabastine[46], loratadine (claritin,
	clarityne)[41,44,49], olopatadine[41,50], mequitazine[47],
	mizolastine[47], pseudoephedrine[51,52], rupatadine[53,54],
	tripelennamine (pyribenzamin)[55]
	Third-generation
	Fexofenadine[37,44,56], levocetirizine[37,39]
H2	First-generation
	Cimetidine[57], metiamide[58]
	Second-generation
	Ranitidine (1979)[59], omeprazole (1982)[60]
	Third-generation
	Famotidine[61], ebrotidine[62], lafutidine[63,64],
	niperotidine[60], nizatidine[60], potentidine[65],
	roxatidine[60], zolantidine[58]
H3	A-304121[66], A-317920[66], 4-(aminoalkoxy)
	benzylamines[67], ciproxifan[66], clobenpropit[68],
	D-alanine-piperazine-amides[69], imidazopyridine[70],
	indole[70], indolizine[70], 4’-[(NR1R2-1-yl)]-propoxy-
	biaryl-4-carboxamides[70], pyrazolopyridine[71],
	1-(4-(phenoxymethyl)benzyl) piperidines[72], SCH
	79687[73], thioperamide[68,74],
H4	JNJ 7777120[75,76], thioperamide[77]