Drug General Information (ID: DDI1QY0FMK)
Drug Name			Dicoumarol		Drug Info		Cholestyramine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anticoagulants				Bile Acid Sequestrants
Structure

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

Recommended Action
Management		Warfarin or other oral anticoagulants should be administered at least one hour before or four to six hours after cholestyramine. The INR or PT should be closely monitored. Patients should be advised to promptly report any signs of bleeding (e.g., pain, swelling, headache, dizziness, weakness, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools) or clots (e.g. chest pain, shortness of breath, sudden loss of vision, or pain, redness or swelling in an extremity).

References
1	Ku LL, Ward CO, Durgin SJ "A clinical study of drug interaction and anticoagulant therapy." Drug Intell Clin Pharm 4 (1970): 300-6.
2	Product Information. Questran (cholestyramine). Par Pharmaceutical Inc, Chestnut Ridge, NY.
3	Wells PS, Holbrook AM, Crowther NR, Hirsh J "Interactions of warfarin with drugs and food." Ann Intern Med 121 (1994): 676-83. [PMID: 7944078]