Drug General Information (ID: DDIWPX4QDY)
Drug Name			Warfarin		Drug Info		Chloral hydrate		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Anticoagulants				Anxiolytics/Sedatives/Hypnotics
Structure

Mechanism of Warfarin-Chloral hydrate Interaction (Severity Level: Moderate)
Competitive binding of plasma proteins Click to Show/Hide Mechanism Graph
Drug Name		Warfarin				Chloral hydrate
Mechanism		Competition for plasma protein binding sites				Competition for plasma protein binding sites
Key Mechanism Factor 1
		Factor Name		Plasma protein binding
		Factor Description		Plasma protein binding refers to the degree of binding of a drug to proteins in the blood, and the lower the degree of binding, the more efficiently the drug can cross cell membranes or diffuse. Plasma protein binding alters the distribution and therapeutic characteristics of the drugs.
Mechanism Description		Increased plasma concentration of Chloral hydrate and Warfarin due to competitive binding of plasma proteins

Recommended Action
Management		Based on these observations, appropriate monitoring for excessive hypoprothrombinemia (INR/PT) is recommended for several days following the addition of chloral hydrate or triclofos to a stabilized regimen of warfarin or other oral anticoagulants. Consideration may be given to using other sedative/hypnotic agents that have not been shown to interact with oral anticoagulants such as benzodiazepines or diphenhydramine. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

References
1	Boston Coll Drug Surv Prog "Interaction between chloral hydrate and warfarin." N Engl J Med 286 (1972): 53-6. [PMID: 5006877]
2	Cucinell SA, Odessky L, Weiss M, Dayton PG "The effect of chloral hydrate on bishydroxycoumarin metabolism." JAMA 197 (1966): 144-6. [PMID: 4161665]
3	Orme M, Breckenridge A, Brooks RV "Interactions of benzodiazepines with warfarin." Br Med J 3 (1972): 611-4. [PMID: 5071697]
4	Robinson DS, Sylwester D "Interaction of commonly prescribed drugs and warfarin." Ann Intern Med 72 (1970): 853-6. [PMID: 5448744]
5	Sellers EM, Koch-Weser J "Potentiation of warfarin-induced hypoprothrombinemia by chloral hydrate." N Engl J Med 283 (1970): 827-31. [PMID: 5458032]
6	Udall JA "Clinical implications of warfarin interactions with five sedatives." Am J Cardiol 35 (1975): 67-71. [PMID: 1109248]
7	Udall JA "Warfarin interactions with chloral hydrate and glutethimide." Curr Ther Res Clin Exp 17 (1975): 67-74. [PMID: 806430]
8	Udall JA "Warfarin-chloral hydrate interaction." Ann Intern Med 81 (1974): 341-4. [PMID: 4855407]
9	Wells PS, Holbrook AM, Crowther NR, Hirsh J "Interactions of warfarin with drugs and food." Ann Intern Med 121 (1994): 676-83. [PMID: 7944078]