mixing warfarin and coumadin

[RI Mom]

Hi All!

It's been awhile since I've been on the site as things have been going well and I was starting to feel like a "normal" mom...LOL anyway, Idrees' INR has been unstable for a few weeks. This week it was downright scary. On Monday, INR was 4.3 so dosage was lowered by 2 mg. total/week and we tested again Friday. Initially I got 9.2 (scary) and thought that it just couldn't be right so I tested again and got 6.4. With such a discrepancy I called Alere and got some advice on technique and tried one more time and got 8.6........WHAT the heck!! I decided to test myself and got 0.8 so that tells me that the machine is not completely out of order but how do you get 3 #'s that are nearly 3 points off when all of these tests took place around the same time?

In going through all of the possibilities with the nurse and pharmacist I remembered that I was mixing Warfarin and Coumadin because of a dosage change. We went to 5 mg. and I just happened to have 2 mg. tabs of warfarin and 1 mg. tabs of coumadin at home so I was combining them to get the 5. Pharmacist said that they don't recommend combining the two but didn't say that INR would be affected that greatly. Anyone ever have a reaction like this to the combination of brand and generic anticoagulants? We are completely perplexed!

 

[catwoman]

Theresa:

They're the same drug, just one generic and the other a TM one. Same color for the same mg strength.
Are you switching to Coumadin or to the generic? Just wondering why you have both types of warfarin on hand.

When I switched to warfarin from Coumadin, I did it by finishing up the Coumadin bottle and plunged cold-turkey into warfarin. Did not have any difference in my INRs. I haven't taken Coumadin brand in probably 5-6 years.

Maybe you should take the ProTime and Idrees to your doctor's office and run a test on the ProTime and then with their machine, hoping they have a CoaguChek or INRatio and that they don't rely on lab draws. That would cause a delay in knowing the "control" INR.

 

[RI Mom]

Unfortunately non of the Ped. Card. clinics have in office INR monitoring. I would have to go to the lab to try to calibrate my machine against their results. I've called some adult clinics but they won't even touch a kid.

I had switched to Warfarin but when the Dr. changed the dose to 5 I just decided to use some 1 mg. tabs that I had from before. that's how I ended up with 2 different scripts.

 

[ALCapshaw2]

Definitely something strange going on here.

I have switched from Brand Name Coumadin to Generic Warfarin from TARO and then later from BARR when suppliers were changed (by insurance company) with NO noticable difference.

I'm wondering if the 'old' warfarin pills were out-of-date OR if they might have been damaged by exposure to humid air (and therefore absorbed some water which may have degraded the tablets). My CRNP's all say to discard out of date pills (and that at 11 cents/pill, it's not worth taking the risk that they are bad).

Your comment that none of the Coumadin Clinics would NOT take a kid caught me off guard.
I can't imagine why NOT.

If your child's INR still tests out of range today, you may need to go to a Hospital Lab and get a vein draw 'just to double check'. Be sure to INSIST that they get the results back to you ASAP (i.e. today).

That said, I'm wondering WHY his INR would have risen so high.
Has he been put on anti-biotics recently?
It would seem prudent to continue to look for an answer to what is going on here
(i.e. is his INR really that high? and if so, what caused that to happen?)

I hope you are able to find some answers.

'AL Capshaw'

 

[dick0236]

Like the others, I am perplexed by what happened. If I understand, you are using two 2mg(warfarin) and one 1mg(coumadin) daily too ge to 5mg? I would suggest an Rx for 5mg tabs. That would eliminate any chance for mixup. I have used warfarin for several years, after being on Coumadin for many years and have found no difference between the brand and generic.

Also, I was told a couple years ago, by a home monitor tech., that once the INR numbers get above 4++, the displayed INR numbers get kind of wacky and it is not uncommon to get wide ranging values.

 

[RI Mom]

Dick, I'm glad that you mentioned about the #'s going above 4 and getting wacky. the tech I spoke to didn't mention that at all. That would make some sense then as to how I could get #'s ranging from 6-9.

He didn't get any ACT for the past 2 nights and I'm going to check him this morning to see what I get. I will likely head to the lab tomorrow to calibrate the machine against the lab to see if we are close. I sure hate to do it because my son gets so darn anxious for the lab draws. I may also try to appeal to my own primary care provider to let me check my results with their INR monitor. I tried once before but didn't speak directly to her, so maybe I can convince her (she's a mom to young kids so I think I'll use that "desperate mom" tactic) I'll let you all know how this turns out week. This poor little boy is tired of me running after him yelling "be careful"!!

 

[RI Mom]

So I just tested him and got 1.6 Normally I give him his ACT at night before bed. Should I give it to him now (morning) instead?

 

[Protimenow]

I, too switched from coumadin to the generic, and have had a few different brands. I checked my INR after making the switch, and there was nothing detectable. And, as others have said, above 4.5 (if I recall correctly), the values could be higher than lab results.

I'm wondering if the pharmacist may have gotten the colors (and dosages) wrong when you got those generics. It sure doesn't sound right to have that kind of a jump. An error at the pharmacy could account for this jump in INRs. If you haven't yet - please confirm that the colors of the pills are what they SHOULD be.

I'm disappointed, too, why no 'adult' doctors or clinics refuse to run a test - for compassionate reasons. You aren't asking them to do any anticoagulation management, and I'm sure that you'd probably sign a release absolving them of responsibility if they ask, and what you're actually doing is asking them to open a window and tell you if it's raining or not -- just a statement of a testable condition. You're looking for a meter reading - not treatment advice.

 

[Bina]

Theresa,
My monitor reads accurately at 4.3 which is the highest I've gone, but if my monitor ever gives me a reading
higher than 5 it should be verified against a vein draw; and in any case at that high a reading I would be taking
a half dose the same day.
You have now seen that by holding doses for 2 days Idrees has had his INR drop drastically.
Some doctors would want him to have a Lovenox shot today, see what your doc says.

 

[ALCapshaw2]

So I just tested him and got 1.6 Normally I give him his ACT at night before bed. Should I give it to him now (morning) instead?

As you have now experienced, Holding Doses for 2 Days often causes INR to Drop Like a Rock!
For an INR above 5.0, holding for one day is certainly not unwarranted.
And yes, meters whose reagents have an exponential mathematical relationship
will show greater 'variation' at the higher numbers.

For Lab Draws, I always ask the technician to use a Butterfly Needle which is very small and feels more like a mosquito bite versus a Bee Sting.
If his arm veins are 'over-used' and he has prominent veins in his hands, that is another option (which I now use).
The Tech at my Coumadin Clinic is SO GOOD that I don't even feel the Butterfly needle.
You might also suggest that your son close his eyes or look away, RELAX the target site, and then tense up his OTHER arm or fist.
(I used this technique ever since tensing my leg before a Booster Shot as a child which was sore for a Week!)

Personally, whenever I find that I have missed a dose, I take my next dose RIGHT AWAY,
then maybe 1/2 of the next dose that night, and the other half dose the next morning,
followed by the regular dose the next night. Works for me.

As others noted, it's still a mystery why his INR got so high.

'AL Capshaw'

 

[Lynlw]

I hope you get things straightenned out. Like the others, I doubt using 2 different brands would have any role in why his INR jumped,(as long as he had no problem with either brand by itself) but since the monitors aren't as reliable, over a higher INR (5?) it would makes sense that you got a big range of results since he was high, often it is recomended to get a blood draw when you have problems like that. to see what his INR really is. I doubt anything is wrong with the machine or that it needs recalibrated, but that it just MY opinion.
Since you said his INR has been unstable for weeks, does that mean they have been making alot of changes, or are you talking about they have been falling in his "normal range" but going from the high to low ends? So they haven't changed his dose?
Maybe it would help to post what he has been getting and what the INR results were since he started having problems.

 

[RI Mom]

I took Idrees to the lab and they got 1.3 so I guess there is nothing wrong with the meter. The Dr's instructions for tonight were to give him 10mg. His typical dose is 6 mg. 4x/week and 4 mg. 3x/week. He was going too low on on that so they up'd it to 6 mg. x4 and 5 mg. x3. He then shot up to 4.3 so the Dr.backed him down to 5 mg. daily and he shot up even more to the 6.3-9.2 range that we got last week. I'm not surprised that he bottomed out after 2 days of no ACT but I didn't think he'd go that low considering his INR was so high. I'm at a loss. I've thrown out the old coumadin tabs that I had and will use only the Warfarin. There are no other meds. that haven't been there all along except I was using a steroid cream (prescribed to me) for some excema. Dr. didn't think it would interact but who knows...this ACT is sensitive, so I've stopped using that as well. We will check again tomorrow after today's 10 mg. dose (which I think is really high). The good news is that my baby has grown up and didn't throw a fit when we got to the lab. He didn't even cry ..... that is such a relief!!

 

[ALCapshaw2]

AARGH !

Overdosing (pre-loading) to bring up INR has been shown to lead to the infamous Roller Coaster Effect.
(and NO, I'm not very impressed with this Doctor).

The NEW guidelines recommend returning to the last stable dose (or estimated stable dose) and just letting the body come up to the desired target range so as not to cause a 'spike' in INR which would then need to be compensated for by Lowering the dose (leading to the infamous Roller Coaster Effect). Some Doctors will recommend using Lovenox injections to prevent clot formation during this transition until the INR is back in range.

Testing only ONE DAY after an increased dose is unlikely to show much of a change since it takes 3 or 4 days for Coumadin / Warfarin to become fully metabolized.

BTW, you need to understand that matching at ONE point is NOT sufficient to confirm the accuracy of a meter over the FULL range. It takes 2 points to define a linear (straight line) relationship and more to define a non-linear relationship (as used in most home test meters).

'AL Capshaw'

 

[RI Mom]

Thanks to this website and the extensive experience of all of you, I have gained enough knowledge to know that the 10 mg. prescribed was going to contribute to the yo yo effect we were getting. I gave him 8 mg. instead on Monday night, checked INR Tuesday afternoon and it was 2.4 so we are going back to the 5 mg. dose and checking in a few days. Holding the dose for 2 days was a mistake. In the future, I would probably hold for one and then give a lower dose on day 2.

Al, I hear what you are saying about waiting several days to check and I suspect that the 8 mg given on Monday will bring him up even further in the next couple of days.

Thanks everyone for you help!

 

[daveguy14]

Theresa,
My monitor reads accurately at 4.3 which is the highest I've gone, but if my monitor ever gives me a reading
higher than 5 it should be verified against a vein draw;

This is right. Everything I've been told is that the home machines lose their accuracy in the high numbers, and so if you get a high reading you need a vein draw to see what it really is.

 

[Protimenow]

Theresa - it sounds like you're getting control of the situation. The advice from 'professionals' is sometimes just not right.

Here's hoping that you've derailed that roller coaster, and the INR will remain within limits from here forward...

Home monitoring, and careful adjustment (without overreaction) of dosage are probably the best advice I can give to get within range and stay within range.