indication

Used as a diagnostic aid for evaluation of gastric acid secretory function

pharmacology

Pentagastrin is indicated as a diagnostic aid for evaluation of gastric acid secretory function. It is effective in testing for anacidity (achlorhydria) in patients with suspected pernicious anemia, atrophic gastritis, or gastric carcinoma. It is also effective in determining the reduction in acid output after operations for peptic ulcer, such as vagotomy or gastric resection.

mechanism of action

The exact mechanism by which pentagastrin stimulates gastric acid, pepsin, and intrinsic factor secretion is unknown; however, since pentagastrin is an analogue of natural gastrin, it is believed that it excites the oxyntic cells of the stomach to secrete to their maximum capacity. Pentagastrin stimulates pancreatic secretion, especially when administered in large intramuscular doses. Pentagastrin also increases gastrointestinal motility by a direct effect on the intestinal smooth muscle. However, it delays gastric emptying time probably by stimulation of terminal antral contractions, which enhance retropulsion.

biotransformation

Primarily hepatic

absorption

Rapidly absorbed after parenteral administration.

half life

10 minutes or less