Coumadin is an anticoagulant medication, also known as a blood thinner, that is used to treat or prevent blood clots in veins or arteries. It works by reducing the formation of blood clots, which can reduce the risk of stroke, heart attack, or other serious conditions. Coumadin may also be used for purposes not listed in the medication guide.

Some key points to keep in mind about Coumadin use include:

• Warnings: You should not take Coumadin if you are prone to bleeding because of a medical condition, if you have an upcoming surgery, or if you need a spinal tap or epidural. You also should not take Coumadin if you are prone to bleeding because of a medical condition, such as a blood cell disorder, ulcers or bleeding in your stomach, intestines, lungs, or urinary tract, an aneurysm or bleeding in the brain, or an infection of the lining of your heart.

• Side Effects: Coumadin increases your risk of bleeding, which can be severe or life-threatening. Get emergency medical help if you have signs of an allergic reaction to Coumadin, such as hives, difficult breathing, or swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any signs of bleeding such as sudden headache, unusual bleeding (nosebleeds, bleeding gums), coughing up blood, or blood in your urine or stools.

• Interactions: Warfarin interacts with many prescription, nonprescription, vitamin, and herbal products. Aspirin, aspirin-like drugs, and nonsteroidal anti-inflammatory drugs (NSAIDs) may have effects similar to warfarin and may increase the risk of bleeding problems if taken during treatment with warfarin. Carefully check all prescription/nonprescription product labels since the products may contain NSAIDs or salicylates.

It is important to closely monitor Coumadin use and to tell your doctor or pharmacist of any changes in medications, vitamins, or herbal products that you are taking. Your doctor or other health care professional should closely monitor you to prevent serious bleeding or clotting problems.