Abstract
To examine whether changes in inhibition of gastric acid secretion occur during chronic ranitidine therapy, duodenal ulcer patients in remission were studied before and after 9 months of maintenance ranitidine therapy (150 mg nocte). At each time, the effect of a bolus i.v. dose of ranitidine (50 mg) on pentagastrin-stimulated maximal acid output was measured. Oral and intravenous pharmacokinetic studies were also performed to examine whether changes in absorption or disposition occur during long-term dosage. After 9 months' therapy, ranitidine inhibited pentagastrin-stimulated secretion by a median of 62%, substantially less than the median inhibition of 95% pre-treatment. Median acid output in the period 60-120 min post-ranitidine was six times the pretreatment value. Since pharmacokinetic parameters were unaltered, this reduced ability to inhibit acid output appears to indicate reduced sensitivity of acid secreting mechanisms to ranitidine after prolonged dosage.
Full text
PDF





Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Aadland E., Berstad A. Effect of cimetidine on pentagastrin-stimulated gastric acid and pepsin secretion before and after 6 weeks of cimetidine treatment. Scand J Gastroenterol. 1978;13(2):193–197. doi: 10.3109/00365527809181747. [DOI] [PubMed] [Google Scholar]
- Barbezat G. O., Bank S. Effect of prolonged cimetidine therapy on gastric acid secretion in man. Gut. 1978 Feb;19(2):151–154. doi: 10.1136/gut.19.2.151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bodemar G., Walan A. Maintenance treatment of recurrent peptic ulcer by cimetidine. Lancet. 1978 Feb 25;1(8061):403–407. doi: 10.1016/s0140-6736(78)91200-x. [DOI] [PubMed] [Google Scholar]
- Gough K. R., Korman M. G., Bardhan K. D., Lee F. I., Crowe J. P., Reed P. I., Smith R. N. Ranitidine and cimetidine in prevention of duodenal ulcer relapse. A double-blind, randomised, multicentre, comparative trial. Lancet. 1984 Sep 22;2(8404):659–662. doi: 10.1016/s0140-6736(84)91224-8. [DOI] [PubMed] [Google Scholar]
- Hetzel D. J., Hansky P. J., Shearman D. J., Korman M. G., Hecker R., Taggart G. J., Jackson R., Gabb B. W. Cimetidine treatment of duodenal ulceration: short term clinical trial and maintenance study. Gastroenterology. 1978 Feb;74(2 Pt 2):389–392. [PubMed] [Google Scholar]
- Ippoliti A., Elashoff J., Valenzuela J., Cano R., Frankl H., Samloff M., Koretz R. Recurrent ulcer after successful treatment with cimetidine or antacid. Gastroenterology. 1983 Oct;85(4):875–880. [PubMed] [Google Scholar]
- Korman M. G., Hetzel D. J., Hansky J., Shearman D. J., Don G. Relapse rate of duodenal ulcer after cessation of long-term cimetidine treatment: a double-blind controlled study. Dig Dis Sci. 1980 Feb;25(2):88–91. doi: 10.1007/BF01308302. [DOI] [PubMed] [Google Scholar]
- Mihaly G. W., Drummer O. H., Marshall A., Smallwood R. A., Louis W. J. High-pressure liquid chromatographic determination of ranitidine, a new H2-receptor antagonist, in plasma and urine. J Pharm Sci. 1980 Oct;69(10):1155–1157. doi: 10.1002/jps.2600691008. [DOI] [PubMed] [Google Scholar]
- Mihaly G. W., Jones D. B., Anderson J. A., Smallwood R. A., Louis W. J. Pharmacokinetic studies of cimetidine and ranitidine before and after treatment in peptic ulcer patients. Br J Clin Pharmacol. 1984 Jan;17(1):109–111. doi: 10.1111/j.1365-2125.1984.tb05010.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peden N. R., Richards D. A., Saunders J. H., Wormsley K. G. Pharmacologically effective plasma concentrations of ranitidine. Lancet. 1979 Jul 28;2(8135):199–200. doi: 10.1016/s0140-6736(79)91466-1. [DOI] [PubMed] [Google Scholar]
