I only have blood tests every 6weeks .In that time my INR varies quite a lot and I drop out of range. I bought a coaguchek machine and I now alter my dose by up to a maximum of 1mg for a day or two either way to stay between 2 and 3 . I've not discussed this with my surgery as when I've mentioned self checking before it's not gone down well.I get the feeling that they consider the machine to be a gadget and certainly not as accurate as there tests (it is , I only ever have a variance of 0.1 ) My question is - is self medicating safe as I think all doses of Warfarin that one takes is registered on a national data base ? What else can you do though when it's only checked every 6 weeks ? I have previously had a TIA and stroke and am obsessive about keeping in range.What would you do?