The present work was conducted in patients with severe
cimetidine-resistant
duodenal ulcer, in order to correlate the response (i. e. healing or no healing of the
ulcer) to
ranitidine therapy and the results of 24 h gastric pH monitoring performed under therapeutic conditions. Twenty patients who fulfilled the criteria of
cimetidine resistance (i. e. with an
ulcer not healed after a treatment with
cimetidine given at a dose of at least 1 g/d for at least 6 weeks) received 150 mg
ranitidine twice daily for 6 weeks and were then controlled endoscopically;
ulcer was healed in 8 cases, not healed in 12 cases. Nocturnal gastric acid inhibition was significantly greater in patients who responded to
ranitidine than in those whose
ulcer did not heal. During daytime the gastric pH profiles were not different between these two groups. Nocturnal pH score was also calculated in each patient by reference to the mean inhibitory effect observed in 8 normal subjects in whom gastric pH was monitored in the same therapeutic conditions. In 7 patients the nocturnal pH score was greater than 10; none of these patients was healed after 6 weeks
ranitidine treatment. Among the 13 patients with a pH score lower than 10, 8 had an
ulcer healed at the end of the
ranitidine course. In 5 cases gastric pH monitoring was repeated after continuation of the
ranitidine treatment; healing of
ulcer was observed in 4 cases, always associated with a nocturnal pH score lower than 10 (in 2 cases after increasing the dosage of
ranitidine).(ABSTRACT TRUNCATED AT 250 WORDS)