Journal
JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS
Volume 28, Issue 6, Pages 539-543Publisher
WILEY
DOI: 10.1111/j.1365-2885.2005.00696.x
Keywords
-
Categories
Ask authors/readers for more resources
Gastrogard(R), an oral formulation of omeprazole, was given to six llamas at a dose of 4 mg/kg once a day for 6 days. Plasma samples were collected at 0, 15, 30, 45, and 60 min and 2, 3, 4, 6, 8, 12, and 24 h on days 1 and 6. Plasma omeprazole concentrations were measured by high-pressure liquid chromatography with ultraviolet detection. Pharmacokinetic parameters calculated included the area under the curve (AUC(0--infinity)), peak plasma concentration (C-max), time of peak plasma concentration (T-max), and terminal half-life (t(1/2)). On day 6, plasma omeprazole concentrations reached a C-max of 0.12 mu g/mL at a T-max of 45 min. The t(1/2) of omeprazole was 2.3 h and the AUC(0--infinity) was 0.38 h.mu g/mL. Plasma concentrations remained above the minimum concentration for inhibition of gastric acid secretion projected from other studies on day 6 in all the llamas for approximately 6 h. However, the AUC(0--infinity) was below the concentrations associated with clinical efficacy. It was not possible to measure oral systemic bioavailability because there was no i.v. data collected from these animals. However, using data published on the i.v. pharmacokinetics of omeprazole in llamas, oral absorption was estimated to be only 2.95%. Due to low absorption the oral dose was increased to 8 and 12 mg/kg and studies were repeated. There were no significant differences in C-max, T-max, or AUC(0--infinity) for either of the increased doses. These results indicate that after 6 days of treatment with doses up to 12 mg/kg, oral omeprazole produced plasma drug concentrations which are not likely to be associated with clinical efficacy in camelids.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available