Ranitidine therapy in patients with idiopathic gastric acid hypersecretion. A prospective study.

One hundred twenty-four patients with idiopathic gastric acid hypersecretion (basal acid output greater than 10.0 meq/hr) were prospectively evaluated and treated with ranitidine twice a day. Fifty-four patients (44%) required standard doses of ranitidine 300 mg/day for adequate treatment, and the other 70 patients (56%) required increased doses of ranitidine (mean 994 mg/day, range 600-3000 mg/day). Mean basal acid outputs for these two groups were 14.0 and 16.6 meq/hr, respectively, which were not significantly different. Nevertheless, there was a significant correlation between basal acid output and daily ranitidine dose required for therapy (r = 0.18, P = 0.05). The duration of ranitidine therapy consisted of: < 1 year (N = 46), 1 year (N = 16), 2 years (N = 19), 3 years (N = 22), 4 years (N = 15), 5 years (N = 6). Only five patients required progressive increases in ranitidine during the time of treatment, which consisted of an average of 0.5 dose adjustments per year. No side effects occurred with any of these high doses of ranitidine. These results indicate that, as in Zollinger-Ellison syndrome, ranitidine is effective therapy for patients with idiopathic gastric acid hypersecretion; however, markedly increased doses as large as 3000 mg/day may be required.