title: Nizatidine suppression of basal gastric acid output: a comparison of two intravenous dosage regimens.
abstract: To study the pharmacokinetics and pharmacodynamics of two intravenous nizatidine dosing regimens, serial plasma concentrations and continuous intragastric pH were monitored simultaneously in 10 subjects with a documented history of duodenal or gastric ulcers. A 24-hour gastric pH profile was characterized for a 300 mg daily dose of nizatidine randomly administered both as 100 mg every 8 hours and 150 mg every 12 hours. No significant differences were observed in the mean pharmacokinetic parameters between the two dosing regimens. Pharmacodynamic parameters for the 100 mg every 8 hours versus the 150 mg every 12 hours regimen were not significantly different except for percent of time during the 24-hour study period that the pH was maintained greater than 4 (43.6 +/- 20.7 versus 34.7 +/- 18.3, P less than .05). A significant relationship was demonstrated for both regimens (P less than .05) between the percent time pH greater than 4 and area under the plasma curve for the 24 hour study period. The lack of a significant difference in nizatidine pharmacokinetics between the two dosage regimens suggests a pharmacodynamic cause for the greater cumulative pH effect of the every 8 hour regimen.
authors.affiliation: College of Pharmacy, University of Illinois, Chicago 60612.
authors.forename: L
authors.initials: L
authors.lastname: Danziger
authors.forename: K M
authors.initials: KM
authors.lastname: Furmaga
authors.forename: K A
authors.initials: KA
authors.lastname: Rodvold
authors.forename: C T
authors.initials: CT
authors.lastname: Bombeck
authors.forename: J H
authors.initials: JH
authors.lastname: Fischer
mesh_terms: D000328:Adult; D000368:Aged; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D006207:Half-Life; D006635:Histamine H2 Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007275:Injections, Intravenous; D008875:Middle Aged; D016567:Nizatidine; D011897:Random Allocation; D013844:Thiazoles / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D006635:Histamine H2 Antagonists; D013844:Thiazoles; D016567:Nizatidine