title: Gastric acid antisecretory effect of two different dosage forms of omeprazole during prolonged oral treatment in the gastric fistula dog.
abstract: Two series of experiments have been performed in gastric fistula dogs to test the antisecretory effect of two different oral dosage forms of omeprazole: 2 mumol x kg-1 x day-1 as a methylcellulose suspension for 8 weeks and 0.5 mumol x kg-1 x day-1 in enteric-coated granules (ECG) for 3 weeks. There was an increasing inhibitory effect during the first days of repeated administration of omeprazole, which is in accordance with its long duration of action. The steady-state inhibitory level was reached after five doses. During the 8-week treatment with the omeprazole suspension (2 mumol x kg-1) the mean maximal inhibitory level (3 h after dose) was 82%, and the mean minimal inhibitory level (24 h after dose) was 35%. With omeprazole in ECG (0.5 mumol x kg-1) the steady-state maximal inhibition (4th h) was 60%, whereas 40% inhibition remained after 24 h. Thus, a more even inhibitory level over day and night seems to be obtained with the ECG formulation than with the suspension. Basal and food-stimulated plasma gastrin levels were not significantly affected by the treatment with 0.5 mumol x kg-1, whereas food-stimulated gastrin levels were slightly increased during treatment with 2 mumol x kg-1. Control levels of acid secretion were reached within 4 days of stopping treatment. In the present studies, in which the inhibition of acid secretion varied over 24 h between approximately 80% and 35% (maximum and minimum), no rebound effects could be detected as measured up to 1 month after cessation of treatment.
authors.affiliation: AB Hässle, Mölndal, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Larsson
authors.forename: H
authors.initials: H
authors.lastname: Mattsson
authors.forename: E
authors.initials: E
authors.lastname: Carlsson
mesh_terms: D000818:Animals; D004285:Dogs; D005744:Gastric Acid / Q000378:metabolism*; D005755:Gastrins / Q000097:blood; D009853:Omeprazole / Q000008:administration & dosage* / Q000097:blood; D012636:Secretory Rate / Q000187:drug effects; D013270:Stomach / Q000502:physiology*; D013997:Time Factors
chemical_list: D005755:Gastrins; D009853:Omeprazole