What beta blocker did you start? My dr started me on carvedilol (coreg) low dose to start and everything was fine, no change. When he saw i no adverse effects from the coreg he had me start doubling my dose till I got to 50mg a day. Did an inr 2 weeks later and ithad spiked to 5.9. Finally got it regulated about a week ago.
Cardiologist said it shouldn't have made a difference, while my thoracic surgeon says otherwise...dr and surgeons almost never agree
Anyway, everyone reacts differently to med's, just keep your eye on it.
Oh, inr in 5 isn't good but not that bad...it needs to get a bit higher to cause major issues. Unfortunately I know from experience.