Use of H2-receptor antagonists in children. H2-receptor antagonists (H2RAs) have evolved into the mainstay of anti-acid therapy for pediatric patients, replacing antacids and other modes of therapy. Much of the experience and data used for therapeutic decisions in children, however, have been extrapolated from adult studies. Ranitidine and cimetidine have been studied most extensively in the adult and pediatric populations. Both raise gastric pH and achieve other therapeutic endpoints; however, cimetidine appears to have a greater frequency of both adversed effects and drug interactions. H2RAs are the preferred agents for prevention of stress ulcers, ulcer disease, and reflux esophagitis in the pediatric population. 