Manual of Clinical Nutrition

Anticoagulant Therapy

Manual of Clinical Nutrition Management III- 5 Copyright © 2013 Compass Group, Inc.

doses up to 800 IU may be safe for individuals taking warfarin, but the evidence is not conclusive (9). Persons
taking or considering taking vitamin E supplements should consult with their physician.

Enteral nutrition: Patients who are receiving enteral nutrition support while on anticoagulant therapy
should be monitored closely. Significant vitamin K intake from enteral formulas can antagonize the effect of
the anticoagulant drug warfarin and result in treatment failure (6). Most enteral formulations contain modest
amounts of vitamin K and provide daily vitamin K intake similar to the average dietary intake from foods (6).
Consistent intake of an enteral formulation containing less than 100 mcg of vitamin K per 1,000 kcal is not
expected to cause warfarin resistance (6,8). However, warfarin resistance can occur in patients on enteral
nutrition support whose intake of vitamin K is substantially low (13). This resistance may occur as a result of
warfarin binding to protein contained in the enteral formula; however, this mechanism has not been
substantiated by clinical data (13,14). A reasonable approach to treating warfarin resistance associated with a
low vitamin K intake is to initiate a trial of holding the enteral nutrition regimen for at least 1 hour before and
after the warfarin dose (13,14).

References

1. Harris J. Interaction of dietary factors with oral anticoagulants: review and applications. J Am Diet Assoc. 1995; 95:580-584.


2. Levine MN, Raskob G, Landfeld S, Kearon C. Hemorrhagic complications of anticoagulant treatment. Chest. 2001; 119 (suppl
   1):108S-121S.


3. Reference values for nutrition labeling. In: A Food Labeling Guide. US Food and Drug Administration Center for Food Safety and
   Applied Nutrition; 1994 (Editorial revisions, 1999). Available at: http://www.cfsan.fda.gov/~dms/flg-7a.html. Accessed October 8, 2007.


4. Booth SL, Centurelli MA. Vitamin K: a practical guide to the dietary management of patients on warfarin. Nutr Rev. 1999; 57(9 pt
   1):288-296.


5. Coumadin [package insert]. Princeton, NJ: Bristol-Myers Squibb Company; 2006.


6. Rollins CJ. Drug-Nutrient interactions. In: Mueller CM, ed. The A.S.P.E.N. Adult Nutrition Support Core Curriculum. 2nd ed. Silver
   Spring, Md: American Society for Parenteral and Enteral Nutrition; 2012; page 309.


7. Vitamin K intake in micrograms by sex, age, and race/ethnicity: United States, 1988–94. In: Dietary Intake of Macronutrients,
   Micronutrients, and Other Dietary Constituents: United States, 1988– 94. National Center for Health Statistics. Vital Health Stat. 2002;
   11(245):102. Available at: http://www.cdc.gov/nchs/data/series/sr_11/sr11/245.pdf. Accessed October 7, 2007.


8. Schulman S. Care of patients receiving long-term anticoagulant therapy. N Engl J Med. 2003; 349:675-683.


9. Important Information To Know When You Are Taking: Warfarin (Coumadin) and Vitamin K. Bethesda, Md: National Institutes of
   Health Clinical Center; 2012.


10. Committee on Safety of Medicine and the Medicines and Healthcare Products Regulatory Agency. Possible interaction between
    warfarin and cranberry juice. Curr Probl Pharmacovigilance. 2003; 29:8.


11. Li Z, Seeram NP, Carpenter CL, Thames G, Minutti C, Bowerman S. Cranberry does not affect prothrombin time in male subjects on
    warfarin. J Am Diet Assoc. 2006; 106:2057-2061.


12. Beatty SJ, Mehta BH, Rodis JL. Decreased warfarin effect after initiation of high-protein, low-carbohydrate diets. Ann Pharmacother.
    2005; 39: 744-777.


13. Petretich DA. Reversal of osmolite-warfarin interaction by changing warfarin administration time. Clin Pharm. 1990; 9:93. Letter.


14. Penrod LE, Allen JB, Cabacungan LR. Warfarin resistance and enteral feedings: two case reports and a supporting in vitro study.
    Arch Phys Med Rehabil. 2001; 82:1270-1273.