Very interesting. I wish someone could have just run a quick test to figure out I was very sensitive to warfarin instead of having the nurse / doctor seem uneasy when they couldn't get my INR down initially.

They are having a really hard time regulating my INR level. I have been as high as 3.1 and as low as 1.6 - I am never consistant. Now they are blaming my recent 1.8 level on me taking Tylenol for a headache. I was told that I could not take ibuprofin but could take acetamiophin. Now I'm being told I can't take anything for a headache. I am so confused.

In any event, I want the genetic testing but my doctor doesn't think it's worth the risk of taking me off the Warfarin. :/

You don't have to go off coumadin for genetic testing. You do for some other types of issues.

Also, 1.6 to 3.1 is really not that wide a range. 3.1 is not significantly out of range and even if you dip a little under two occasionally you still have protection.

There are a few small studies that show there may be some effect on INR from acetaminophen in some people. They show an increase in INR though not a decrease. If that is true for you, you would need to monitor your INR and adjust your dose. I personally take acetaminophen daily without it affecting my INR. As with everything else, you need to balance benefit vs. risk.

http://www.ncbi.nlm.nih.gov/pubmed/21923443

I just commented on another discussion thread that the variances you're experiencing with your INR are truly minor, and very common, and not sure why your doc is trying to blame it on these things that really generally have minor impact. I take tylenol and never experienced any issues from it with my INR. I think what you are experiencing is completely normal for a lot of people when they first start warfarin and it just takes a while to dial into the write dosage for your body. None of this seems unusual. Aggravating, yes. Abnormal, not so much.

Sheesh, I meant RIGHT, not WRITE, dosage.

It's more then just annoying to have INR levels all over the place. It means I have to go to the anticoagulation mgt. clinic at the hospital once a week. I get frustrated because I don't even want this medication. I stated in another thread that I'm not really seeing the reason for ME personally to be on a 6 month treatment. If they really think it's the estrogen then I'm off of that. My PFT was excellent. My lungs are clear. I feel I'm being held captive by a medication.

It's like how most schools place all children in the same box instead of trying to teach the child in a way that's best, they teach to the test. It's protocol. It's how it's done. I think they should look at each individual persons case and treat the illness based on need. Instead it's protocol.

I still want the genetic testing done but was told that I have to be off the Warfarin because it can influence the results. If that's not the case then that's great. I'll have it done.

jan is partially right. Some of the blood tests can be done while on warfarin, but not all of them.

I think they're being a little weird about the tylenol too. I've never had an issue with it.

Protocols are developed for your safety. They research to see what is the most likely treatment to keep you alive with the minimum of side effects.

I do remember how I disliked going in so often at the beginning of my treatment before I stabilized. I guess now I just accept it. Mostly I go in monthly but then something throws me out of whack and I'm back to weekly. Right now I'm on antibiotics so it is back to weekly. I get tested at a cancer clinic so going in is good for me in other ways. Seeing all the people going in for chemo makes me realize how small my problems are.

There are genetic tests affected by coumadin use? Which ones? What is the mechanism?

It is my understanding that the tests for antibodies for acquired immune disorders or for protein levels that indicate a possible genetic condition are affected by a recent clotting incident and by taking coumadin. A DNA analysis though shouldn't be affected by these things.

The original post is referring to tests of DNA to look for specific mutations that affect metabolism of coumadin. That would not be affected by current use of coumadin. The very interesting links in the original post (Thanks Cave!) do lead me to believe that this type of testing might be worthwhile in the elderly population who are more at risk of poor outcomes.

Whether it is worth doing genetic testing for hypercoaguable states is addressed by the article at the link.

http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/hematology-oncology/hypercoagulable-states/

I wasn't talking just about the genetic testing (genes aren't affected by warfarin). I was just saying that there are some blood tests that could indicate a clotting disorder that ARE affected by warfarin. Most hemos will run tests after you're off, just to make sure they can do them all.

The ones I'm fairly sure that should NOT be done while on warfarin of are Antithrombin Deficiency, and the Protein C and S Deficiencies.

Right, the original post was about DNA testing to see how your body processes warfarin, not the genetic testing to see if you have a clotting disorder. Two completely different things, at least that's what I'm understanding.

I agree with Jan that the DNA testing would be most appropriate for certain at risk populations, not for every single person who goes on warfarin. It would be expensive and probably not considered medically necessary for all warfarin patients.

For the first 5 months I was on warfarin, I had to got the lab once a week because my INR was so stubborn. It's a pain in the ass, but really, it's not that big of a deal in the overall scheme of thing.

I work full time, I have a busy life, I have responsibilities etc and still have managed to live well, have a great life, and just get through it despite trips to the lab and being on warfarin. I think this stuff takes over you life only if you let it.

Also, no one puts a gun to your head to take medication. If you don't want to take it, don't. I think that would be a foolish decision but it's ALWAYS your choice what you decide to take or not to take.

I can only go by what I'm being told at the AMC (anticoagulation management clinic). 3.1 made them nervous for bleeding risks. 1.6 was too low and I had to do the heparin (sp) injections 2.5 is ideal for me. I have taken so many different dosages. Thank goodness they write it down for me on a card so that I can keep track of what I'm supposed to be taking.

The interesting thing about the insurance companies is that you would think they would try and drive the bus a little bit. My hospital stay was $65,000 my insurance paid for all but $1,700 of it. My weekly testing can't be cheap. I'm still waiting for a summary on that expense. My doctor visits are not cheap either and all of the follow up testing that I have to have done. So, why wouldn't they want genetic testing?

Well, my understanding is that genetic testing is ridiculously expensive and won't guarantee that you'll be able to dial in the perfect dosage right away. So, you'll still have to do at least SOME of those tests and doctor's visits.

And, for me, since I usually stabilize in a week or so (except after surgery) the genetic testing would be pretty much useless. IMHO.

I guess I should clarify ...

The genetic testing can clearly be quite useful, I just don't think there's a reason to order it across the board for every warfarin patient. Still, its definitely a tool that docs should know about.

My mom actually participated in a study that shows your sensitivity to coumadin/warfarin. She has a heart condition and is not currently on anticoags, but her cardiologist asked if she'd like to be tested when she went for her 6 mo exam. We don't have results back yet, but we're very excited about this, and she has FVL hetero! My father's side of the family (grandfather, himself, and now me) are very sensitive to coumadin and have FVL hetero - I hit 4.9 and dad hit 8.4 within the first two weeks of taking it. It would have really helped us out. My grandfather is now in a nursing home, cannot self-advocate, is a fall risk, and we were able to tell the nursing staff so his INR didn't go sky-high when they started him on it.

Do think everyone should automatically be tested who takes warfarin? No, that's not efficient. Do I think people with genetic clotting disorders should have the option? Yeah. Over the course of a lifetime, the cost of one test can more than make up for extra tests and doctor visits.