Food/Drug/Supplements that effect INR

Common drugs that can interact with warfarin include:

Aspirin or aspirin-containing products
Acetaminophen (Tylenol, others) or acetaminophen-containing products
Antacids or laxatives
Many antibiotics
Antifungal medications, such as fluconazole (Diflucan)
Cold or allergy medicines
Ibuprofen (Advil, Motrin IB, others) or naproxen sodium (Aleve, Naprelan, others)
Medications that treat abnormal heart rhythms, such as amiodarone (Pacerone, Nexterone)

scan for more information on drug interaction:

drug interactions with Warfarin
drugs that interact with warfarim

Common supplements that can interact with warfarin include:

Vitamin K
Vitamin K2 [2]
Vitamin C [3]
Probiotics [2]

Resveratrol (possibly safe, see [1])
Omega 3
Coenzyme Q10 (ubiquinone)
Dong quai
Ginkgo biloba
Green tea
St. John’s wort
Vitamin E
Vitamin A
Senna leaves
Flavonoids – safe [4]
Vitamin D3 – reduce vitamin K

Take Magnesium/Zinc/Iron at least two hours apart from Warfarin That should eliminate any possible interaction.

Common foods and drinks that might interact with warfarin include:

Food high in Vitamin K (green leafy vegetables)*

Cranberries or cranberry juice
Black licorice

It’s important to have a consistent amount of vitamin K in your diet (if on warfarin). If you have little vitamin K in your diet, a sudden spike can increase your risk of bleeding.

Resistance to oral anticoagulants has been associated with high vit K food intake.

Foods rich in vitamin K include:

beef liver, broccoli, Brussels sprouts, cabbage, collard greens, endive, kale, lettuce, mustard greens, parsley, soy beans, spinach, Swiss chard, turnip greens, watercress, and other green leafy vegetables.

Moderate to high levels of vitamin K: asparagus, avocados, dill pickles, green peas, green tea, canola oil, margarine, mayonnaise, olive oil, and soybean oil. Snack foods containing the fat substitute,

olestra, are fortified with 80 mcg of vitamin K per each one ounce serving

Consumption of large amounts of mango fruit has been associated with enhanced effects of warfarin. The exact mechanism of interaction is unknown but may be related to the vitamin A content, which may inhibit metabolism of warfarin.

Limited data also suggest a potential interaction between warfarin and cranberry juice resulting in changes in the INR and/or bleeding complications.

There have been several case reports in the medical literature of patients consuming grapefruit, grapefruit juice, or grapefruit seed extract who experienced increases in INR. R(+) warfarin…possibly safe

.. elevated INR due to pomegranate juice

Black currant juice and black currant seed oil may theoretically increase the risk of bleeding or bruising if used in combination with anticoagulants.

Soy protein in the form of soy milk was thought to be responsible for a case of possible warfarin antagonism in an elderly male stabilized on warfarin. The exact mechanism of interaction is unknown, as soy milk contains only trace amounts of vitamin K. Subtherapeutic INR values were observed approximately 4 weeks after the patient began consuming soy milk daily for the treatment of hypertriglyceridemia. No other changes in diet or medications were noted during this time. The patient’s INR returned to normal following discontinuation of the soy milk with no other intervention.

An interaction with chewing tobacco was suspected in a case of warfarin therapy failure in a young male who was treated with up to 25 to 30 mg/day for 4.5 years. The inability to achieve adequate INR values led to eventual discontinuation of the chewing tobacco, which resulted in an INR increase from 1.1 to 2.3 in six days. The authors attributed the interaction to the relatively high vitamin K content in smokeless tobacco.

Some experts recommend that continuous enteral nutrition should be interrupted for one hour before and one hour after administration of the anticoagulant dose and that enteral formulas containing soy protein should be avoided. Anticouglant users should consider limiting the consumption of cranberry juice or other cranberry formulas or pomegranate juice, black currant juice, and black currant seed oil.

<h2) Natural blood thinners</H2
Celery, galic, vit C
are does Warferin alternativesss,
need some postapocaliptiiic solution, assumin, only

Other blood thinning medication:

Plavix – avoid grapefruits, Celery
לתרופות החדשות למניעת קרישה (קסרלטו, אליקוויס ופרדקסה) כמעט שאין התנגשויות ידועות עם מזון.
avoid grapefruits, Celery, garlic

לבני ממליצה גם להיזהר ממזונות מדללי דם כמו סלרי ושום ולא לצרוך אותם בכמויות גדולות, למרות שכרגע אין מידע על אינטראקציות של מזונות אלה עם התרופות החדשות.




[3] Vitamin C
Vitamin C with Rose Hips (ascorbic acid)

Ascorbic acid has been implicated in causing warfarin resistance. However, controlled clinical trials have not demonstrated clinically important variations in prothrombin times. The possibility of an interaction may be considered if warfarin resistance is encountered in patients taking high doses of ascorbic acid.
Smith EC, Skalski RJ, Johnson GC, Rossi GV “Interaction of ascorbic acid and warfarin.” JAMA 221 (1972): 1166
Hume R, Johnstone JM, Weyers E “Interaction of ascorbic acid and warfarin.” JAMA 219 (1972): 1479
Rosenthal G “Interaction of ascorbic acid and warfarin.” JAMA 215 (1971): 1671
Weintraub M, Griner PF “Warfarin and ascorbic acid: lack of evidence for a drug interaction.” Toxicol Appl Pharmacol 28 (1974): 53-6
Feetam CL, Leach RH, Meynell MJ “Lack of a clinically important interaction between warfarin and ascorbic acid.” Toxicol Appl Pharmacol 31 (1975): 544-7

[4] = flavonoids, no interaction with Warfarin –


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