Drug General Information (ID: DDIDSYBFX4)
Drug Name			Pantoprazole		Drug Info		Gefitinib		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiulcer Agents				Antineoplastics
Structure

Mechanism of Pantoprazole-Gefitinib Interaction (Severity Level: Moderate)
Altered gastric pH Click to Show/Hide Mechanism Graph
Drug Name		Pantoprazole				Gefitinib
Mechanism		Gastric alkalinizer				Gastric pH sensitive
Key Mechanism Factor 1
		Factor Name		Gastric pH
		Factor Description		The normal pH range of gastric acid is between 1.5 and 3.5 and is highly acidic, consisting mainly of hydrochloric acid. Changes in the pH of the stomach can alter the absorption of drugs.
Mechanism Description		Decreased absorption of Gefitinib due to altered gastric pH caused by Pantoprazole

Recommended Action
Management		The possibility of a diminished therapeutic response to gefitinib should be considered during coadministration with H2-receptor antagonists or proton pump inhibitors. Pharmacologic response to gefitinib should be monitored more closely whenever one of these agents is added to or withdrawn from therapy.

References
1	Product Information. Iressa (gefitinib). Astra-Zeneca Pharmaceuticals, Wilmington, DE.