Foods you need to be careful with Drug Interaction (2)

Foods you need to be careful with Drug Interaction (2)

Foods you need to be careful with Drug Interaction (2)

We are often directed to take medicines after each meal. However, the medicine may interact with food within a body, and work less effectively, or cause a dangerous side effect.

Even the food that is known as healthy for our body, there are dangerous combinations with some medicines. We need to be careful not to take these foods too much at once.

In this article, as following the previous article “Foods you need to be careful with Drug Interaction (1),” we will talk about the dangerous drug interaction with vegetables and fruits.

Broccoli before taking antithrombotic medicine may cause thrombus, and make your blood vessel easily clogged up

Warfarin potassium (Product name: MAREVAN), used as antithrombotic which has been used for a long time to make blood flow fluent, often interacts with food. Especially the foods with rich vitamin K coagulate blood and weaken the effectiveness of medicine. This function may cause thrombus in blood and the risk of myocardial infarction or cerebral stroke.

Example(s) of foods that contain rich amount of vitamin K: Indian spinach, turnip leaves, pea sprouts, garland chrysanthemum, brassica rapa, spinach, leaf mustard, rosette bok choy, cilantro, broccoli, parsley.

It is not necessary to stop taking the food with rich amount of vitamin K completely just because they are not compatible with medicines. Vitamin K is an essential, nutrient and healthy bones as it prevents an osteoporosis by remineralizing bones. 

Most dangerous condition to be considered is when taking excess amount of vegetables with vitamin K at once or repeatedly for many days in a row. It is preferable to take small amount everyday to avoid the risks yet taking an essential amount of vitamins.

Cabbage before taking antipyretic analgesic/anti asthmatic metabolizes the medicational nutrients and makes them ineffective

Antipyretic analgesics such as acetaminophen (or paracetamol) are known as incompatible with brassicaceae vegetables such as cabbage and broccoli. This is due to the nutrient called glucuronic acid which helps medicine to excrete out of your body faster.

Brassicaceae vegetables are also known for its function of increasing metabolic enzymes in river. Thus it may reduce the efficacy when taken with antitussive which contains theophylline.You do not need to be worried if the amount is a small side dish size but it is deemed to be careful if excessive amount.

Example(s) of brassicaceae vegetables: Cabbage, Japanese mustard spinach, brassica rapa, napa cabbage, broccoli, mizuna greens, cauliflower, radish sprouts, radish, watercress, kale, rosette bok choy.

Example(s) of medicine which contains acetaminophen: Antipyretics: Panadol, etc.

Cold medicines: Panadol Cold & Flu, etc.

Example(s) of medicine which contains theophylline: Apo-Theo LA, etc.

Maitake mushroom/Mango before taking antithrombotic improves blood flow and leads to the risk that bleeding would not stop

Beta-glucan contained in mushrooms is known to make blood flow fluent. When taken with warfarin potassium which is an antithrombotic with same efficacy, the doubled effect may occur. Also, as pointed out in blow, the nutrients of mushroom dissociate the medicine from protein within blood and strength the efficacy. Supplements with mushroom essence also lead to the excessive intake of beta-glucan. Please consult your doctor or pharmacist before taking antithrombotics. 

Interaction of warfarin within blood and mushroom essence

When warfarin is attached with protein: Medicine does not work effectively under this condition. When warfarin is apart from protein: medicine works under this condition.

Example(s) of mushroom that strengthens the warfarin efficacy: Maitake mushroom, bunashimeji mushroom.

Another case reported is that a warfarin potassium habitual user keeps eating mangoes, same as maitake mushroom, bleeding does not stop easily when injured. This mechanism is not determined yet, but the possibility of vitamin A contained in mango is pointed out to reduce metabolic enzyme in river. There is no need to be worried as long as having mangoes for small amount as a desert, but it is deemed to be better to avoid eating repeatedly like everyday.

Interactions of warfarin  and vitamin A

  1. Warfarin is metabolized by CYP.*
  2. Vitamin A interferes the function of CYP.
  3. Warfarin does not get metabolized, the medicational efficacy gets strong.

      *Please refer the details of CYP in “How food and beverage interfere with your medications (1).”

Example(s) of foods that contain rich amount of vitamin A: Mango, eel, black cod, river, pumpkin, molokhia.

Does maitake mushroom cure cancer?

Some cancer patients take supplements extracted from mushroom essences, believing it has an anti-cancer effect. But there is no clear basis on this brief, and FDA(Food and Drug Administration) is warning to stop selling the supplements that are declaring “a cancer will be vanished.”

We need to remember that mushrooms have healthy potentials but no nutrient to cure a cancer.


In this article, we discussed about the compatibility of vegetables and fruits with the certain medicines. We hope you now have the idea that there are incompatible combinations of medicine and the food that we are eating everyday without paying any attention.  

Those who take warfarin, particularly, need to be careful with the food selection. It is often the case that many of warfarin intakers with bad results on blood test often eat meals that contains rich amount of vitamin K.

We want to keep in mind to eat moderate amount.

In next article, we will continue talking about the compatibility of medicine with vegetables and dairy products.

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