Yeah, sometimes INRs do that for no apparent reason. Sometimes too, as you start feeling better, you tend to get more active and that can affect your INR. 1.8, while not "therapeutic" , is not terribly low so I would try not to worry too much.

Warfarin is a funky drug and dosage changes are a part of it, especially in the beginning. That's why we have to get our INRs checked regularly.

Thanks RMB, do you think 2 weeks is a good follow up time after testing low?

As rmb says, 1.8 isn't dramatically outside the usual target 2-3 range so a check in 2 weeks with a small alteration to your dose sounds fine. A variation like this is fairly normal.

Like rmb said, my INR seemed to drop as I got better and got more active. Dropping from 2.2 to 1.7 in a week, with no major changes in diet. My INR was never the most stable, but I made it thru my 6 months on warfarin, and had no clotting or bleeding issues. A small tweak in dosage and check back in 2 weeks after a reading of 1.8 seems fine to me.

Thanks RMB and Edmie.. I am feeling better about the follow up. I my leg is feeling great and it doesn't seem to be swelling. Sometimes it's hard to tell what you are actually feeling and what is all in your mind.

My INR yo-yo's like crazy. I would say being more active seems to effect it. Its frustrating I find the better i feel the worse my INR is. When my INR is ideal i feel gross.

Coumadin is such a fickle drug, eating, drinking, exercising and even taking other medications can and do affect your PT/INR and how your body metabolizes your Coumadin. Sometimes we don't even think abut anything we may have eaten or drank that is different. About a year ago I discovered a really nice Huckleberry wine and on occasion I have a small glass. Nothing big and not a lot or often. However last week I had a small glass and checked my PT/INR the next day and found I had dropped from a 2.8 down to a 1.5 in 1 week. I wasn't really worried and really neither was my doctor however he told me not to have anymore wine until my pro-time came back up, who would have thought a small glass of huckleberry wine could so affect my levels. Normally I wouldn't have even noticed this as I was on a 1 month check but since I am just coming back onto Coumadin and have to be at strict levels I am down to checking my PT/INR weekly.
Hope this helps shed a little light on this silly fickle drug.
Hugs
Ferr

OH and I found my activity levels did at first mess with my PT/INT but once I got leveled back out on my activity levels my pro-times also leveled out. Just remember don't limit your activities or change your eating habits unless your doctors recommend it, have the doctors adjust your Coumadin to your activity and eating habits. Life is way to short to sit back and watch the world go by
hugs
Ferr

Ferr-- I went for a visit with my hematologist on Wednesday. She wanted to do a CBC and a CNP (I think this is the liver/kidney function) and it came back at 1.7.. I am a little concerned at this point that something has changed in my metabolism or liver function to affect it downward. She told me to up the dose from 9mg to 12mg for 3 days and then go back to 9mg, and follow up with INR on Monday

There's nothing wrong with you. This is very common when you are first on warfarin.

Gotta agree with RMB. INRs tend to fluctuate, which is why we all have to test so frequently. They can change even if you've been on warfarin for a while.

I've been on warfarin for about four years at this point. Last year, for some reason, the dose I'd been on for three years started being too much. I was testing in the 3s and 4s. We dropped my dose. Now, a year later, I've been stable on the new dose. Then ... the last couple of months it hasn't been quite right anymore and my INR is dropping too low. We're still adjusting.

But, both of those major fluctuations didn't have any obvious cause. Something about the alignment of the planets, I guess.

There's nothing wrong with you or your major organs that is causing the fluctation in INR. Being sick can affect your INR, taking other meds and vitamins can affect your INR, being more active can affect it, eating different foods can affect it. Unless you stay locked in a glass box and never get sick and always eat the same food, your INR will change. Hopefully it fluctuates IN range, but it won't always do that. You'll adjust your dose and go on with life. Not worth worrying about ... its just part of the joy of warfarin.

Thanks everyone for your responses. I never used to worry about things, now I find myself overthinkimg everything.

Remember too that when you are first on warfarin, your INR numbers may reflect how your living at that moment, which is just out the hospital, low energy, low activity, sleeping more, you may not be eating as much etc. So once you settle back into a more normal routine, where you're maybe eating more, have more energy, are more active in terms of going places, chasing kids around, working, whatever, that INR dosage that you were initially on may need to be adjusted to account for that.

My INR took quite a while to stabilize and stay at two or above after I was out of the hospital. My INR wouldn't budge while in the hospital and so I was given a large dose to boost it up so I could be discharged and then put on 7.5 mgs after that to start with, a base line dosage. Within 5 months of that I was up to 15mgs a day because my INR was just so stubborn. Since then over a span of 6 years, I've been on everything between 11mgs and 15mgs, or a combination thereof. I'm on 14mgs a day right now. It's really a matter of trying to dial into a dosage that is going to work for where you're at right now in your lifestyle.

It's not worth the energy or stress of trying to pinpoint why it's happening. Everyone's body processes the drug differently and it's just a weird drug. Try not to sweat this so much.

My mental issue with it is that when I am lower than 2.0, I feel like it is not working and these clots we are trying to resolve are going to start growing again and potentialy break off and send another one up to my lung. Is the dfference between 2.0 and 1.7 really that great, or is my thought process just flawed.

A normal person's INR is usually between 0.9 and 1.1, so even at 1.7, you are still way more anticoagulated than the average guy on the street.

In fact, some people have done low-dose warfarin as a preventive measure (I think between 1.5 and 1.8), so it isn't like your body will instantly start clotting if you drop below 2.0.

The ideal zone is between 2.0 and 3.0 (or, for some, between 2.5 and 3.5) but people sometimes have it set higher or lower for different reasons. I mean, you don't want to stay at 1.7 for months on end, necessarily, when you're dealing with recent clots but you're certainly still protected to some extent at that level.

Also, don't think of warfarin as working or not working. It's just more or less, like with the volume on the radio or the heat in your house. A lower INR means less effect, for sure, but it doesn't mean NO effect until you get down around 1.0.

So, while 1.7 is something to address with your doc and resolve, it doesn't mean you're suddenly in danger, either.