several agents are under investigation in the u.s. , including other h2-receptor antagonists ( famotidine and nizatidine ) , proton-pump inhibitors ( omeprazole ) , prostaglandins ( misoprostol , arbasprostil , enprostil , and trimoprostil ) , antimuscarinic agents ( pirenzepine ) , and tricyclic antidepressants ( doxepin and trimipramine ) .
C2757005
h2-receptor
C0015620
famotidine