Some patients are on blood thinners for their medical conditions like DVT, Pulmonary embolism, Post Valve replacement, to prevent stroke in patients with atrial fibrillation (an irregular heart rhythm) etc.
Anti-platelet drugs like aspirin, clopidogrel, prasugrel, ticagrelor and cilostazole do not come in to this category of blood thinners and they don’t need any specific dietary alterations.
Among the blood thinners, there are relatively recent drugs like Dabigatran, Rivoroxaban and Apixaban which are together called newer oral anticoagulants (NOACs) which don’t need any specific dietary alterations.
The blood thinners belonging to Coumarin group of drugs which include Warfarin, Acitrom (Acenocoumarol) etc are also known as vitamin K antagonists (VKAs). Patients on these drugs need some dietary restrictions and instructions to keep the total daily intake of vitamin k stable so that there will be no fluctuations in the action of these drugs.
If these drugs act more they may cause bleeding manifestations and if they act less, they may not be able to prevent the clotting of blood defeating the purpose of their intake.
There is no need to completely avoid all foods containing vitamin K and doing that might even be detrimental. Consistency in the daily intake of vitamin K is the key.
Some common foods that are low in vitamin K are:
- Eggplant (Brinjal)
- Cucumbers (raw)
- Most fruits including Strawberries, Apples, Peaches, Watermelon, Pineapple, Bananas, papaya, raisins, dates, figs, apricot.
- Most roots and tubers including potatoes, Beet root, Carrots, Sweet Potatoes
- Most Non-Vegetarian food except Egg yolk and Liver
There is no need for any dietary restrictions while taking these foods that are low in vitamin k.
When we are taking foods that are high in vitamin K levels, we need to take them in moderation and in consistent portions daily (and week to week) (amounting to about 60 to 80 mcg of Vitamin K per day) and should avoid a sudden increase or decrease in their intake.
Some common foods that are high in vitamin K are:
- Leafy vegetables like Spinach (Paalak), Parsley (dhaniya), Collard greens (Kaanul haak), Mustard greens (Sarason ka saag), Green lettuce (a type of Paalak), Amaranth leaves, garden cress etc
- Cabbage, Cauli flower, Broccoli, Kale (Karamsaaag – a type of gobhi), Brussels sprouts (choti gobhi)
- Endive (gulsuchal)
- Legumes like Beans, Soya beans
- Okra (bhindi)
- Kiwi fruit
Patients on VKA blood thinners should also avoid drinking:
- Green tea
- Grapefruit juice
- Cranberry juice
Green tea contains vitamin K and could lower the effectiveness of Warfarin. Drinking grapefruit juice, cranberry juice, and alcohol during treatment with Warfarin can increase your risk of bleeding.
In addition to food, many other substances can interact with warfarin. These include medications, supplements, and herbal products.
Some medications that can interact with warfarin include:
- antibiotics such as ciprofloxacin or fluconazole
- certain birth control pills
- certain drugs for seizures
- anti-inflammatory drugs such as ibuprofen
- antidepressants such as fluoxetine
- other blood thinners such as aspirin, clopidogrel, or heparin
- certain antacids
Supplements and herbal products that can interact with warfarin include:
- Gingko biloba
- Goji Berries
- Horse Chestnut
- Melilot (Sweet Clover)
- Red Clover
- Willow Bark
- Wheat Grass
- co-enzyme Q10
- St. John’s wort etc.
Also, some patients receive b-complex or calcium tablets as co- prescriptions. Some of them contain Vitamin K also. Patients may take only vitamin k containing supplement and not exceeding 100% of RDA (recommended daily allowance)
Patients on such herbal supplements or multivitamin drugs should discuss with their doctor regarding their use.
Also, PT-INR, the test done to find out the efficacy of the VKA blood thinners may fluctuate after an inter-current illness. So, they should if needed have an unscheduled check up of PT-INR during the inter- current illness and if needed modify the dose of the medication.
– Dr. P. Nagaraj Kumar, Consultant Cardiologist