Premium
Ranitidine kinetics and dynamics: II. Intravenous dose studies and comparison with cimetidine
Author(s) -
Lebert P A,
Mahon W A,
MacLeod S M,
Soldin S J,
Fenje P,
Vandenberghe H M
Publication year - 1981
Publication title -
clinical pharmacology and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.941
H-Index - 188
eISSN - 1532-6535
pISSN - 0009-9236
DOI - 10.1038/clpt.1981.201
Subject(s) - cimetidine , ranitidine , medicine , kinetics , pharmacology , quantum mechanics , physics
Intravenous ranitidine has been shown to reduce pentagastrin‐stimulated gastric secretion. Eight normal men received, in randomized order, 60 mg ranitidine or 300 mg cimetidine intravenously over 2 min. Both ranitidine and cimetidine induced decreases in volume hydrogen ion content and pepsin activity of stimulated gastric juice. Ranitidine half‐life (t½) was 2.1 ± 0.1 hr and cimetidine (t½) was 1.5 ±0.1 hr. Ranitidine volume of distribution was 1.6 ±0.1 l/kg and that of cimetidine was 1.12 ± 0.12 l/kg. The clearance of ranitidine was 0.54 ± 0.04 l/kg hr −1 and that of cimetidine was 0.5 ± 0.05 l/kg hr −1 . It is suggested that the intravenous loading dose of ranitidine necessary to attain a serum concentration of 200 μg/l (which would achieve a 50% inhibition of gastric acid) is 0.3 mg/kg, followed by an infusion rate of 0.11 mg/kg hr −1 . Clinical Pharmacology and Therapeutics (1981) 30, 545–550; doi: 10.1038/clpt.1981.201