Vitamin E can do the same.
That is not a reason to avoid these healthy supplements, but rather add them slowly into your regimen with monitoring by your doctor to allow for dosage adjustments of the anticoagulant. Add only one new supplement at a time between blood tests and report any signs of easy bruising. Also, don't be afraid to let your doctor know you are interested in taking supplements, so that it can be noted in your record. The opposite challenge may occur when adding green, leafy vegetables like spinach, kale, beet or mustard greens or herbs such as alfalfa, nettles and dandelion to the diet. These are all rich in vitamin K which is used to produce prothrombin and causes increased clotting ability.