Drug General Information (ID: DDIXTGVL9D)
Drug Name			Didanosine		Drug Info		Levofloxacin		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anti-Hiv Agents				Antibiotics
Structure

Mechanism of Didanosine-Levofloxacin Interaction (Severity Level: Moderate)
Complex formation Click to Show/Hide Mechanism Graph
Drug Name		Didanosine				Levofloxacin
Mechanism		Polyvalent cations				Binds to polyvalent cations
Key Mechanism Factor 1
		Factor Name		Chelation
		Factor Description		Chelation is a direct drug interaction that usually involves the formation of dimers or trimers, resulting in larger complexes and poorer absorption.
Mechanism Description		Decreased absorption of Didanosine due to formation of complexes caused by Levofloxacin

Recommended Action
Management		Levofloxacin should be administered at least 2 hours before or 2 hours after didanosine buffered tablets or pediatric oral solution, and patients should be monitored for potentially decreased antimicrobial efficacy during concomitant therapy. Didanosine buffered powder for oral solution, which uses a citrate-phosphate buffer, and the delayed-release capsules, which are not buffered, are not expected to cause this interaction.

References
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