Warfarin and Blood

[BernardS]

some take 5+ mg daily for an INR of 2.5 Some 1 mg daily. Does this say anything about your blood or liver function??

[Hidden]

INR is affected both up and down by so many factors that it is surely going to be difficult to pinpoint exactly why some people need a high dose and others get by with taking very little Warfarin. What prompts your selection of blood or liver function? Surely these are equally complex subjects.

Even a simple question like what's your dose and how many steps on average do you take per day will be flawed if we fail to add in 'and are you a cyclist?'

[BobD Volunteer]

No. It is about how each individual metabolises the drug. We are all different and it has nothing to do with what we might call liver function. I know of otherwise healthy people taking 14mg to attain an INR of 2.5. The amount we take is of no importance. Only the resulting INR.

[BernardS in reply to BobD]

Thanks BobD.I can rest easy now.

[Hidden]

Not sure I understand your post ... so for what it's worth the answer is no! That said, my GP carries out annual blood tests for kidney, liver function based on reactions to all the meds I am taking.

[BernardS in reply to Hidden]

I suppose what I am asking is ' does your blood group have any bearing on the amount of Warfarin to be taken to reach INR of 2.5.

[Hidden in reply to BernardS]

Blood group influences stroke risk with O having least risk, but I had not heard of a link between blood group and level of Warfarin dose.

[Hidden]

Aaaaah! well I'm no expert but I pretty much imagine that the answer is no.

John

[MarkS]

It is possible to predict initial warfarin loading using genetic tests, so it would seem that your genes play a significant role. I think it's relatively little to do with kidney/liver function.