Drug General Information (ID: DDIPUCY9XW)
Drug Name			Colestipol		Drug Info		Digitoxin		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Bile Acid Sequestrants				Antiarrhythmic Agents
Structure

Mechanism of Colestipol-Digitoxin Interaction (Severity Level: Moderate)
Complex formation Click to Show/Hide Mechanism Graph
Drug Name		Colestipol				Digitoxin
Mechanism		Anion exchange resin/polymer				Binds to anion exchange resin/polymer
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 Colestipol due to formation of complexes caused by Digitoxin

Recommended Action
Management		Digoxin should be administered at least one to two hours before or four hours after colestipol. It may be prudent to monitor patients for altered clinical response and to monitor digoxin levels. Patients should be advised to notify their physician if they experience worsening of their heart symptoms. Conversely, patients should be monitored for digoxin toxicity if colestipol is discontinued.

References
1	Bazzano G, Bazzano GS "Digitalis intoxication. Treatment with a new steroid-binding resin." JAMA 220 (1972): 828-30. [PMID: 5067348]
2	Heel RC, Brogden RN, Pakes GE, Speight TM, Avery GS "Colestipol: a review of its pharmacological properties and therapeutic efficacy in patients with hypercholesterolaemia." Drugs 19 (1980): 161-80. [PMID: 6988203]
3	Neuvonen PJ, Kivisto K, Hirvisalo EL "Effects of resins and activated charcoal on the absorption of digoxin, carbamazepine and frusemide." Br J Clin Pharmacol 25 (1988): 229-33. [PMID: 3358884]
4	Product Information. Colestid (colestipol HCI). Pharmacia and Upjohn, Kalamazoo, MI.
5	Rodin SM, Johnson BF "Pharmacokinetic interactions with digoxin." Clin Pharmacokinet 15 (1988): 227-44. [PMID: 3056649]