Interactions

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Protimenow

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I've referred to some published drug interactions in other forums.

Here's a link to a published paper that has good material on plant based items that do, may, and probably don't interact with warfarin. The text is interesting, and there's also a chart that summarizes the information. (I avoid grapefruit, am very cautious with cranberry (if I ever have it), and stay away from fermented soy and soy milk.

 

tom in MO

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First thing listed on the table is cranberry listed as severity:major. I looked into this a few years ago since I like cranberries. I found out that it was not well founded. The warning for cranberries appears to trace back to a few instances of intense cranberry juice drinking and speculation. I have a glass of cranberry juice about 2 times a week with no problems and also eat cranberry based products.

Cannabis is also listed as severity:major. There's a lot of people on warfarin that smoke and eat pot.

I wouldn't put much faith in that reference
 

Warrick

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I don’t think the legitimacy of the reference should be in question, rather different things effect people differently, look at grapefruit, Ive read here people eating it with no issue and others their INR goes sky high, same goes with alcohol.
 

marvsehn

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First thing listed on the table is cranberry listed as severity:major. I looked into this a few years ago since I like cranberries. I found out that it was not well founded. The warning for cranberries appears to trace back to a few instances of intense cranberry juice drinking and speculation. I have a glass of cranberry juice about 2 times a week with no problems and also eat cranberry based products.

Cannabis is also listed as severity:major. There's a lot of people on warfarin that smoke and eat pot.

I wouldn't put much faith in that reference
Been there 50 years ago, but I wouldnt say there are a lot or people on warfarin using dope. Sorry. I personally dont know of any.
 

tom in MO

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Been there 50 years ago, but I wouldnt say there are a lot or people on warfarin using dope. Sorry. I personally dont know of any.
There's been people here who have reported that they use pot. A search on the word marijuana gives 5 pages.

With medical and recreational use of it being legal in many states plus Canada, and it being recommended for many common comorbidities, I am sure that people on warfarin successfully use pot w/o any problems. If there was an interaction, our cardiologists would be warning us.
 
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tom in MO

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I don’t think the legitimacy of the reference should be in question, rather different things effect people differently, look at grapefruit, Ive read here people eating it with no issue and others their INR goes sky high, same goes with alcohol.
I definitely think the legitimacy of the reference should be questioned. There is a lot of misinformation out there about warfarin. This reference doesn't pass a simple check of personal experience and an internet search of other information sources. A quick check on the publisher shows their revenue stream comes not from subscriptions (there can't be any since they are open source) but from charging the authors. That's not conducive to good peer review and accurate information.

Alcohol does not affect your INR unless you drink so much you puke out your warfarin. I was told by doctors and pharmacist that the reason why they used to tell people to stay off the booze if on warfarin is because they may fall down and hurt themselves.
 
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Protimenow

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Tom: The fact that you regularly drink cranberry juice doesn't disprove the idea that there are interactions. Because you regularly drink it, you're probably already using the dose of warfarin that adjusts for any interaction.

I wonder if an occasional drinker (or binger) on the stuff would have a similar experience.

As far as alcoholic beverages are concerned, it's probably safe to conclude that alcohol, as an individual item, doesn't affect INR. We went through this on this site a few years ago. There is a component of red wines - the darker they are, the more this may affect INR - that may influence INR. People who drink a lot of Red wine may do well to test their INR the day after drinking a lot of the stuff.

As far as marijuana is concerned - I have seen nothing regarding with interactions with warfarin.
 

Warrick

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If I drink 3-4 355ml beverages at around 4.5% alcohol volume every day for 3-4 days my inr goes up over 4.0. I dont drink often so it is easy to identify this as a factor.
Thats why everyone is different.
You are absoutely right there is a ot of mis information, and like a lot of myths the truth is in there somewhere.
 

tom in MO

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When judging this reference, remember they rate cranberry and pot as "severity:major" which is defined by them as
Major​
Death, major bleeding, entailing entire cease of warfarin therapy​

Not true for cranberry and pot.

They also list Garlic, Grapefruit, Chamomile and Ginseng as "major". You'd think if it was "death, major bleeding, etc." they would be putting warning labels on these things, especially in California.
 

LondonAndy

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Of course, one plus of self testing is that we can cautiously experiment. I had avoided grapefruit because of the warnings, but when these posts started recently on here I experimented. I checked my INR was mid-range, and had a small quantity of grapefruit segments in juice. I tested my INR the next day, and again 3 days later, maintaining my normal diet as closely as possible to try and make the grapefruit the only thing that had changed. In my case I had a slight increase (0.2) in INR the next day, and another 0.1 higher at day 3. These are small changes that, in my opinion, might have happened anyway, but if they ARE down to the grapefruit then they are minor. I am glad to be having the occasional small portion of this fruit again, especially now it is summer!
 

Thomas

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I'm still trying to find out what dietary products actually affects my INR. It's only been a year and a half since surgery.

The only thing that I've avoided is grapefruit which I don't like, so no problems.
I don't drink much however, on occasion I've had too much to drink with no effects either way on my INR. I've used marijuana products (it's legal here) with no ill INR effects.
I am not a vegetarian but we eat "in my opinion, not my wifes" a lot of greens - no effect.
I make a great Kale and Sausage dish that we have often; again, no effects. Other than that one dish, I'm not a fan of kale so I keep telling my wife I need to avoid it. So far so good.

I realize everyone metabolizes things differently but the only thing that I find is that if my warfarin dosing is adjusted - even slightly - my INR will crash or spike depending on which way the dose is adjusted.

I'm at the point now that I really don't even think of being concerned with what I'm eating from an INR perspective.
 

Thomas

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I was just reading the report that Protimenow posted. I'm not a scientist or research analyst but The Cannabis paragraph says
"....There is no experimental evidence for interaction between warfarin and Cannabis [37]. However, a clinical case report described a raised INR and bleeding in a patient who smoked Cannabis (2.5 packs/day for 35 years) while taking warfarin [38]."
Table 3 above it lists Cannabis as having potential for major effects as Tom in MO noted.

It looks like they've based their findings on theory and one case; which in my mind is questionable to start with based on the description they offer. Cannabis is not sold in packs like cigarettes and OMG, there isn't enough time in a day for that amount of consumption. Trust me, in my younger days I tried... Normal functionality would be impossible even with increased tolerance over time.

I realize we all need to be cautious with what we put in our bodies but this seems alarmist to me. It leads to questioning the credibility of the report when reading this type of limited speculative analysis.
 

tom in MO

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I was just reading the report that Protimenow posted. I'm not a scientist or research analyst but The Cannabis paragraph says
"....There is no experimental evidence for interaction between warfarin and Cannabis [37]. However, a clinical case report described a raised INR and bleeding in a patient who smoked Cannabis (2.5 packs/day for 35 years) while taking warfarin [38]."
Table 3 above it lists Cannabis as having potential for major effects as Tom in MO noted.

It looks like they've based their findings on theory and one case; which in my mind is questionable to start with based on the description they offer. Cannabis is not sold in packs like cigarettes and OMG, there isn't enough time in a day for that amount of consumption. Trust me, in my younger days I tried... Normal functionality would be impossible even with increased tolerance over time.

I realize we all need to be cautious with what we put in our bodies but this seems alarmist to me. It leads to questioning the credibility of the report when reading this type of limited speculative analysis.
I think the key thing to note is the author pays the publisher, Hindawi, to be published. There's no incentive for true peer review or to reject a paper that on face value is incorrect.
 

Protimenow

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I didn't carefully check the source for this report and, in retrospect, probably should. If this was a paid article, without peer review, it may be suspect. The article listed many references - and I haven't checked them out.

What I was mostly interested in was interaction with non-prescription items. There's a dearth of information out there. I thought some of this may be informational, if not somewhat helpful.

Old advice may also help -- be consistent in diet, test after making changes, adjust dosing to accommodate for changes caused by dietary modifications.

Having a meter makes this easy.
 

carolinemc

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I don’t think the legitimacy of the reference should be in question, rather different things effect people differently, look at grapefruit, Ive read here people eating it with no issue and others their INR goes sky high, same goes with alcohol.
Just the thing is to be consistent on anything you eat and drink. I don't eat salads often, so when I do it close to test, it will raise my INR. Otherwise, just eat and drink what you normally do. Consistency is very important. Hugs for today.
 

carolinemc

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Of course, one plus of self testing is that we can cautiously experiment. I had avoided grapefruit because of the warnings, but when these posts started recently on here I experimented. I checked my INR was mid-range, and had a small quantity of grapefruit segments in juice. I tested my INR the next day, and again 3 days later, maintaining my normal diet as closely as possible to try and make the grapefruit the only thing that had changed. In my case I had a slight increase (0.2) in INR the next day, and another 0.1 higher at day 3. These are small changes that, in my opinion, might have happened anyway, but if they ARE down to the grapefruit then they are minor. I am glad to be having the occasional small portion of this fruit again, especially now it is summer!
What you are advised by doctor professionals is cranberry juice more than anything. There is an enzime that can mess with your INR. Just ask your cardio or other medical professional on what they know what you should be consistent on your daily intake. I never go by so called medical articles unless they are in New England Journal of Medicine. Reliable sources. Hugs for today.
 

tom in MO

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Just the thing is to be consistent on anything you eat and drink. I don't eat salads often, so when I do it close to test, it will raise my INR. Otherwise, just eat and drink what you normally do. Consistency is very important. Hugs for today.
Actually I believe that variety is the spice of life and the secret to good nutrition. A consistent diet of meat and potatoes is what has lead many cultures into obesity. Variety in your diet was taught to me by a nutritionist and also in cardiac rehabilitation. For example, eat fruit, vegetables, meat, fish, grains, dairy, insects :) but all in moderation. In cardiac rehab, the buzz word was to make sure your dinner is colorful, not monochromatic and to go "Mediterranean diet" if you are to lean in any one direction.
 

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