I'm so thankful for this forum as you really do begin to believe you're going crazy when every health professional says that warfarin is not the cause of weight gain since the start of your treatment. Whether it's the actual drug or how it interacts in your body or the cause of taking your warfarin, obviously based on all the testimonials here and on other sites, there ARE side effects that they are not willing to admit to. Or, they simply have not done the research or surveys to clinically support this. Regardless, while I hate this weight gain, I feel a little better knowing that I'm not imagining it. I work out 5-6 days a week and watch what I eat and still the weight creeps on. Siigghhh