Warfarin & One A Day Vitamins

Coumadin, generically called warfarin, acts as an anticoagulant, serving as an antagonist of vitamin K, also known as the clotting vitamin. Your doctor may prescribe warfarin to prevent the formation or growth of blood clots. Warfarin may also be prescribed for patients with mechanical heart valves or certain types of heart arrhythmia. Depending on the nutrient content, dietary supplements can reduce or enhance the effectiveness of blood thinning medications such as warfarin and may cause serious complications. If you take warfarin, the contents of some One A Day products may be a concern.

One A Day

Vitamin K is of particular concern for individuals taking warfarin. Because vitamin K can counteract the blood-thinning effect of warfarin, it's important to keep your intake of this nutrient consistent, according to the National Institutes of Health. The nutrient content of One A Day vitamins varies by product. While One A Day Essentials lacks vitamin K, the Men's Health and Women's formulas provide 20 mcg and 25 mcg of vitamin K, respectively. Tell your doctor about any dietary supplements you take. You may be advised to avoid supplements containing vitamin K while taking warfarin.

Herbal Supplements

Warfarin may be counteracted by certain herbal ingredients, including ginger, fish oil, turmeric, garlic, ginkgo biloba and St. John's wort. Such herbs should be avoided when taking blood thinning medication prior to surgery, according to the Cleveland Clinic. One A Day Women's 50 Plus Advantage, for example, contains 120 mg of ginkgo biloba extract. Check with your doctor before taking any supplements that include herbal ingredients.

Other Concerns

Vitamin E may have blood-thinning properties. Taken in high doses of more than 1,000 international units, or IUs daily, vitamin E may increase your risk of excessive bleeding, according to the National Institutes of Health. High intakes of vitamin E, in combination with warfarin, may be particularly problematic. One A Day products generally provide less than 100 percent of the recommended dietary allowance of vitamin E, which ranges from 22.4 IU to 28.4 IU for adults. However, your doctor is the best resource for coordinating your supplement needs with your medication needs.

Considerations

One A Day supplement products provide a range of nutrients. Although it is necessary to properly manage vitamin K intake while taking Warfarin, other nutrients and herbal ingredients may also warrant close monitoring. Your doctor should routinely check your International Normalized Ratio and Prothrombin Time to make sure your medication is working properly and determine if changes in your dosage or diet are needed.