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

Mechanism of Didanosine-Lomefloxacin Interaction (Severity Level: Moderate)
Complex formation Click to Show/Hide Mechanism Graph
Drug Name		Didanosine				Lomefloxacin
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 Lomefloxacin

Recommended Action
Management		Lomefloxacin should be administered at least 2 hours before or 4 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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6	Product Information. Videx (didanosine). Bristol-Myers Squibb, Princeton, NJ.
7	Sahai J, Gallicano K, Oliveras L, Khaliq S, Hawley-Foss N, Garber G "Cations in the didanosine tablet reduce ciprofloxacin bioavailability." Clin Pharmacol Ther 53 (1993): 292-7. [PMID: 8453847]
8	Shiba K, Sakamoto M, Nakazawa Y, Sakai O "Effects of antacid on absorption and excretion of new quinolones." Drugs 49(Suppl 2) (1995): 360-1. [PMID: 8549362]
9	Shimada J, Shiba K, Oguma T, et al "Effect of antacid on absorption of the quinolone lomefloxacin." Antimicrob Agents Chemother 36 (1992): 1219-24. [PMID: 1329615]
10	Damle BD, Mummaneni V, Kaul S, Knupp C "Lack of Effect of Simultaneously Administered Didanosine Encapsulated Enteric Bead Formulation (Videx EC) on Oral Absorption of Indinavir, Ketoconazole, or Ciprofloxacin." Antimicrob Agents Chemother 46 (2002): 385-91. [PMID: 11796346]