Warfarin is sold under the brand names Coumadin® and Jantoven®. Your doctor will tell you how much warfarin to take to treat your condition. Take warfarin at the same time every day. You can take warfarin with or without food. If you miss a dose of warfarin, check with your doctor or your health care provider at your anticoagulation clinic about when to take your next dose. Never double a dose of warfarin to make up for a missed dose unless you are told to.