Warfarin dosage program.

[seasider18]

Is there an online program I can download to calculate warfarin dosage.

[BobD Volunteer]

Why would you need to? Are you not under a warfarin clinic? Short answer is no as we are all different or it would be easy wouldn't it. Many people play around with  their own doses  I know (How did I suddenly go to italics) with a Coagucheck machine but in my view that way danger lies.

[jeanjeannie50 in reply to BobD]

The italics came on in a post I did recently.  All very strange!

[seasider18 in reply to BobD]

Yesterday my reading had gone from 2.8 to 3.1 and the nurse reduced my dosage from 8mg to 7.9 eg. 7.5mg yesterday and 8mg for the rest of the week. I found a chart that said if INR went into the range 3.1 to 4.0 the dosage should be decreased by 5-10% for the next week.

I thought that it would be interesting to compare surgery dosage with another source.  

uwhealth.org/files/uwhealth...

[MarkS]

I self-monitor and self-manage - i.e. I test and make the dosage adjustments myself.

The evidence indicates that self-monitoring is better than standard anti-coagulation clinic care and that self-management is even better than self-monitoring.

However you do need to understand warfarin and its effect on you personally. That means finding the dose which you're reasonably stable on. For me that's 8.5mg p.d. I then adjust that 0.5mg up if my INR drops below 2.2 and 0.5mg down if it's above 2.8. That way, testing weekly, I manage 99% time in range (2.0 - 3.0).

You don't need a warfarin program. I would suggest that if you go this route you may need to test more frequently initially. 

[Hidden in reply to MarkS]

That's really good Mark - 99% - I am managing 93% at the moment. Yes, I too tweak my own doses when I need to. Normally that's mostly on a trip to Australia when the travel and general lifestyle changes seem to cause my INR to become a tad unstable. When I get back to UK and settle back into my normal routine it all goes back to normal.

Currently I'm on 8 weekly (56 days) INR checks.

John

[BernardS]

I have been managing my own INR levels using a CoaguChek machine for a couple of years. My INR range is 2.0 - 3.0 however to my dose is only 1.5 mg daily so adjusting my dose when levels are outside the limits is a bit more difficult because a .5mg  change is in actual fact a 30% change for me. That being said my average over the last eight months is 2.52 so it can be done. During that time my highest reading was 3.1 and lowest 1.8  I use common sense not a chart and manage fine. 

[seasider18 in reply to BernardS]

I always feel that the INR nurse is restricted by her dosing sheet from doing anything but a tiny adjustment when sometimes more is required.

When previously on Warfarin my reading went from 2.1 to  3.1 my dosage was reduced from 7.1 to 7.0 daily. the next week my reading was 3.9 and it was reduced to 6.4. I did some research and found that as I had been prescribed Amiodarone that my dosage should have been reduced by 25% in each of the next two weeks. It was only after six weeks when the dosage was reduced to 5mg that my INR went to 2.6

The cardiologist who had prescribed Amiodarone had not said this and neither the nurse or my GP were aware of the Amiodarone effect. I asked the pharmacist why she had not warned me and she replied she thought everyone knew that. 

[Witchypoo2]

I self manage my INR using a Coagucheck, although I still have my INR checked at my clinic every three or four months just to make sure my machine is accurate. My GP has been very supportive.  I have an Apple app quite simply called "WarfarinGuide" which I have never had to use (but is very simple to use) as my INR is very stable between 2.4 and 2.7. I love my Coagucheck as it gives me freedom. 

[seasider18]

I had another INR surge after having my last cardioversion. It was 2.6 when going for it and five days later it was 3.7 and the only medication change was that bisoprolol had been stopped.

[ILowe]

This is only second hand. But I know a nurse whose practice uses a program. But the trouble is, the program they use only looks at the previous result, and is incapable of looking at overall trends. So she often over-rules it.

I have been self-dosing for 23 years. I had two minutes training + the odd comment at irregular checkups. I have had to handle singlehanded, coming back onto warfarin after coming off it and having the heparin bridge, taking antibiotics that affected severely the INR and not even having a baseline and knowing I was unstable (no testing available), and start/stop of Amiodarone, etc, all without medical help.

It is not that difficult!

1. Tolerate a wider range: I aim for 3-4, but tolerated 2-5. Anything inside this band does not merit a dose change. *Premature dose changes create and magnify swings*. I think that incompetent health professionals who do not seem to understand this are making things worse for many people.

2. Expect regression towards the mean

3. If you must make a dose change, make it a small one

The best explanation I have found on the web is: m.hopkinsmedicine.org/hemat...

It really is first rate. Take a look

[seasider18]

One of the practice nurses sticks to whatever comes up on her screen. The other considers it and will over rule it or seek advice..

Did you know to adjust your dosage when you started Amiodarone ?

I was started on both when in hospital after my valve replacement with Warfarin at 4mg and for the first few weeks was monitored by the hospital until stable. After stopping warfarin and later going back on it my GP followed a rule that said to start on 10mg for the first two days and then 8mg until reaching my target.

  

[ILowe in reply to seasider18]

Two nurses with different habits. Now you know better than to take verbatim the advice of your practice nurses. Listen to it by all means, perhaps negotiate, but decide who has the final say.This is easier said than done. It is relatively easy for me because I have been self dosing for over 20 years. If that excuse does not work, I say that I decide in consultation with my wife, who is a nurse. Over thirty years ago last in paid work (hush hush). Ah, that seems to reassure them even more!!

Yes, before I started Amiodarone I googled it, found that most descriptions were too vague, found one accurate description, then found someone had copied that to Wikipedia. What is missing is accurate information on coming off Amiodarone. In a few weeks time I will post my data. I was not warned. When I later said to the doctor I should have been warned, he said, since I was in total control of my warfarin there was no need to warn me!

Why did you stop warfarin for a valve replacement? Was it because you had a natural valve? With metalic valves you are on it for life.

Many years ago I was told by someone working in cardiology at Papworth, Cambridge, that I must NEVER start high then reduce. "Don't do it" was his urgent plea. I had just had the heparin bridge for surgery, and the doctor locally had re-started warfarin at the normal dosage, and, sure enough, two days later, it kicked in at roughly the right level. Starting high could have resulted in a dangerous swing to a high level. References are available.

The advice your GP gave could be one more example of old advice.

[seasider18 in reply to ILowe]

I posted in another conversation that I can no longer find that I woke with a bloodshot eye last Wednesday prior to going for my INR check. The nurse said that if it worsened in the next few days to see my GP.

It was worse on Friday and I phoned Specsavers to ask if they would have a look at it. They said as it was probably medication related to see my GP.

I had intended to leave it until Wednesday when I have an ophthalmology appointment at the hospital for an ongoing eye problem but on Sunday it looked like pool of blood in my lower eye when I pulled the lid down.

I went to see the doctor today and he said that I was right to come as that bleeds can often lead to an infection and that the blood usually pools like that. He gave me antibiotic eye drops (Chloramphenicol) to use four times a day for five days and to stop warfarin for a week and then go back to my usual dose.

[ILowe in reply to seasider18]

You say you have had a valve replacement. Was it made of metal, or something natural? You never stop Warfarin for a week if you have a metal valve.

Yes, bleeds can be a problem, especially in the first year or so of being on Warfarin. You do well to seek prompt advice if you spot a serious bleed, and anything in the eyes needs checking.

But, bloody eyes can happen for many reasons. The most common is an eye infection. We know it locally as 'red eye' and where I live the phamacist will quickly look and give you the drops without needing a prescription. I would certainly not stop warfarin for just that, though I would quickly test the INR and make sure I was not hugely out of range.

[seasider18 in reply to ILowe]

I just replied to you and stopped to check something and it disappeared. It will now need to wait until tomorrow.

[ILowe in reply to seasider18]

Take your time. On forums I too sometimes lose messages -- I have an internet that cuts without warning unless there is activity, and writing a message does not count!! So I usually make sure I copy the message to my clipboard saver (clipmate) before submitting then losing. Keep well.