Effects of ranitidine bismuth citrate on gastric acid secretion and gastrin release in subjects with and without Helicobacter pylori infection.
BACKGROUND
Ranitidine bismuth citrate is a novel antiulcerant that provides the antisecretory activity of ranitidine and the gastric mucosal protection and antibacterial properties of bismuth.


METHODS
This randomized, double-blind, placebo-controlled study evaluated the effects of single doses of ranitidine bismuth citrate 200 mg, 400 mg and 800 mg and ranitidine hydrochloride 150 mg on gastrin release and suppression of gastric acid secretion, and compared acid secretory profiles and gastrin release between Helicobacter pylori-negative and -positive patients. Plasma gastrin concentrations were determined by radioimmunoassay under basal conditions and in response to peptone meal stimulation. Acid secretion was measured under basal conditions and in response to peptone meal stimulation. Presence of H. pylori was determined by both 14C-urea breath test and ELISA serology.


RESULTS
Inhibition of gastric acid output by ranitidine bismuth citrate was both time- and dose-dependent over the 9-h post-dose study period. Doses of ranitidine bismuth citrate 400 mg and ranitidine hydrochloride 150 mg, which are equimolar, produced similar suppression of acid output regardless of H. pylori status. Ranitidine bismuth citrate had no effect on plasma gastrin concentrations regardless of H. pylori status. All doses of ranitidine bismuth citrate were well tolerated.


CONCLUSIONS
Ranitidine bismuth citrate caused time- and dose-dependent reductions in meal-stimulated and between-meal gastric acid output regardless of H. pylori status. The magnitude of decreased acid secretion was similar with ranitidine bismuth citrate 400 mg and ranitidine hydrochloride 150 mg. Ranitidine bismuth citrate had no effect on plasma gastrin concentrations.
Ciociola
A A
AA
Glaxo Wellcome Inc., Research Triangle Park, NC 27709, USA.
Webb
D D
DD
Heath
A
A
Walsh
J H
JH
D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000863:Antacids / Q000494:pharmacology*; D001729:Bismuth / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005502:Food; D005744:Gastric Acid / Q000378:metabolism*; D005753:Gastric Mucosa / Q000187:drug effects* / Q000378:metabolism*; D016481:Helicobacter Infections / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D016480:Helicobacter pylori; D006635:Histamine H2 Antagonists / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010461:Peptones / Q000494:pharmacology; D010919:Placebos; D011899:Ranitidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D013268:Stimulation, Chemical
D000863:Antacids; D006635:Histamine H2 Antagonists; D010461:Peptones; D010919:Placebos; C073340:ranitidine bismuth citrate; D011899:Ranitidine; D001729:Bismuth