It's usually 2-3 but I know some people are lower and some are higher, depending on their situation.

Not sure if it depends on the country, but it may depend on whether you have a clotting disorder, and what kind.

rmb, thanks for your reply.

While I was in the hospital they did not test me for clotting disorders. They will probably do it after my 6 months check, I suppose.

Therefore, I don't know why I should be in this higher range...

Yeah boy, I honestly don't know why the higher range. I'd definitely find out from the folks managing your warfarin.

Echo, I think sometimes it's kind of just a discretionary thing for the doctor. Normal INR range is 2.0-3.0, but there are protocols for when to place a patient in higher range, usually it's like rmb said, for known clotting disorders.

But I know that while I started in a 2.0-3.0 target range, my doctor didn't like me on the lower end of that either because of the severity of my clotting, he always said he'd rather have me too high as opposed to too low. Basically I was at best just barely 2.0, and lots of times I was below and he ended up switching me to the higher target range of 2.5-3.5, even at that, he preferred for me to be on the higher end of that.

I hadn't had testing for disorders yet at that time, but they said due to the severity of the clotting and because my body reacted to warfarin "like I had a clotting disorder" they kept me higher.

So it may not necessarily be just a thing that's different by your country (although it could be too - sometimes there are different medical protocol in different countries), it might just be your doctor's decision based on your circumstances, that he thinks the higher range is safer for you. But I agree that you can certainly ask the doctor why, just to know, but I don't really think at the end of the day it's so important. My doctors even now (I'm on permanent treatment) prefer that my INR stay above 2.5, so we usually shoot for between 2.5-3.0. But when you're talking treatment for around the six month time frame, that extra .5 (above 3.0) isn't likely going to make much difference one way or the other.

My doctor wants me in the 2.5-3.5 range, as well, and is happiest when I'm hovering around 2.8-3. I have apparent clotting disorders on both sides of the family. I had huge amounts of clot in both lungs, and no apparent DVT.
My mother, on the other hand, had numerous small clots. She also has a familial bleeding disorder on top of her familial clotting disorder. She only takes 1mg of warfarin a day, and her doc wants her in the 2-2.5 range, preferably more toward 2.1 than 2.5. Guess what? We have the same doctor! So it's doctor discretion a lot of times, based on your personal situation. You could ask your physician, though. That would satisfy your curiosity better, because only he/she knows why that decision was made.

Thanks a lot for all the replies. I will enquire further at the thrombosis centre that treats me as an outpatient.