2 an increased risk of osteoporosis Warfarin suppresses Vitamin K, which is necessary for calcium absorption... Vitamin D shortage I had my vitamin D, B-12, iron, and thyroid levels checked. Except for my vitamin D, everything has returned to normal, and I'm still taking Warfarin and staying within the typical range. I'm apprehensive about continuing to take Warfarin in the event of a stroke. My primary care physician says there are no studies showing that it increases the risk of strokes but that there may be other risks associated with it. She recommends that if you're going to continue taking Warfarin, then it's better to do so under a doctor's supervision. The most common side effect of Warfarin is bleeding from any body cavity or orifice. If you're taking Warfarin for heart surgery or another invasive procedure, you may be at increased risk of bleeding. Talk with your doctor about what kind of monitoring you'll need while you're taking Warfarin. There are also interactions between Warfarin and other medications you may be taking. Make sure you tell your doctor if you're taking any other drugs for heart conditions, blood thinners, pain relievers, antibiotics, or acid reflux medication. Not only does Warfarin have many side effects, but it also has a lot of interactions with other medications. It's important to work with your doctor to find an alternative treatment plan if you experience any symptoms of a stroke while on this drug.