Drug General Information (ID: DDI52YV0FI)
Drug Name			Didanosine		Drug Info		Atazanavir		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anti-Hiv Agents				Anti-Hiv Agents
Structure

Mechanism of Didanosine-Atazanavir Interaction (Severity Level: Moderate)
Altered gastric pH Click to Show/Hide Mechanism Graph
Drug Name		Didanosine				Atazanavir
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 Atazanavir due to altered gastric pH caused by Didanosine

Recommended Action
Management		Atazanavir should be administered, with food, 2 hours before or 1 hour after didanosine buffered formulations. Didanosine delayed-release capsules are not buffered and are not expected to cause this interaction. However, because didanosine should be administered on an empty stomach, the capsules should also be administered at different times from atazanavir.

References
1	Cerner Multum, Inc. "Australian Product Information.".
2	Product Information. Reyataz (atazanavir). Bristol-Myers Squibb, Princeton, NJ.