I feel the same way. It is insane have to take 4ever since av replacement. Will be 4 yrs in March on 6mg. Inr not always stable sometimes have to stop taking for a few days. Really feeling 93 instead of 39. Dr.'s say I shouldnt feel this way and been tested for everything. Dr.s feel it is stress and anxiety. I have extreme fatigue, leg cramps, high back pain, twitchy eyes and fogginess, forgetfulness and absolutely no energy to do anything. I am also losing my hair and my headaches are far more severe than before. Even getting stiff neck, stiff joints hard to get up when have to. Limp around. I understand I have to take this since I have a mechanical valve but no one told me it would be so bad what quality of life is this?! I have kids and cant even have fun with them. I am just alive and grateful for it. But this is hell if you ask me.