Generic Name: Warfarin

  • What is this medication and its most common uses?

    Coumadin is a blood thinner used to treat blood clots and prevent the development of new clots in your body.

  • What should I know when beginning and continuing on this medication?

    How does this medication work?

    Coumadin blocks the formation of substances in your body that help form blood clots, thereby lowering the chance of blood clots developing.

    What are the beneficial effects of this medication and when should I begin to have results?

    What: By lowering the chance of blood clots forming in your body, Coumadin reduces your risk of having a stroke, heart attack, or other serious conditions.

    When: Coumadin may start working within 1 to 3 days.

    How do I know it is working?

    Your healthcare provider will order a blood test to check how well your medication is working. This blood test is called an INR test. The INR test checks to see how fast your blood clots. Your healthcare provider will decide what INR numbers are best for you. Your dose of Coumadin will be adjusted to keep your INR in the target range determined by your healthcare provider.

    Eat a normal, balanced diet while you are taking Coumadin, as this will also affect the results of your INR test.

  • What are the possible side effects of this medication?

    The following is not a full list of side effects. Side effects cannot be anticipated. If any develop or change in intensity, tell your healthcare provider as soon as possible. Only your healthcare provider can determine if it is safe for you to continue taking this medication.

    Coumadin can cause bleeding that can be serious and sometimes life-threatening. You may have a higher risk of bleeding if you take Coumadin and are 65 years of age or older; have high blood pressure, serious heart disease, low blood cell counts, cancer, kidney problems, or a history of stomach or intestinal bleeding, stroke or mini-stroke, or trauma (such as an accident or surgery); or also take other medicines that increase your risk of bleeding (such as heparin, nonsteroidal anti-inflammatory drugs [NSAIDs] [such as ibuprofen or naproxen], or other medicines to prevent or treat blood clots).

    Call your healthcare provider right away if you develop pain, swelling, discomfort, headaches, dizziness, weakness, unusual bruising (bruises that develop without known cause or grow in size), nosebleeds, bleeding gums, bleeding from cuts that takes a long time to stop, menstrual bleeding that is heavier than normal, pink or brown urine, red or black stools, are coughing up blood, or if you vomit blood or material that looks like coffee grounds.

    More common side effects may include: bleeding.

    Less common side effects may include:

    Destruction of skin tissues or development of gangrene (death of tissue in part of the body), with symptoms such as pain or changes in color or temperature in any area of your body.

    Purple toes syndrome with symptoms such as pain in your toe(s) or purple or darkly colored toe(s).

  • Who should not take this medication?

    Do not take Coumadin if you are allergic to it or any of its ingredients.

    Do not take Coumadin if you are pregnant, unless you have a mechanical heart valve.

    Do not take Coumadin if your chance of having bleeding problems is high. Your healthcare provider will decide if Coumadin is right for you.

  • What should I tell my healthcare provider before I take the first dose of this medication?

    Tell your healthcare provider about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Coumadin. Also, talk to your healthcare provider about your complete medical history, especially if you fall often; have high blood pressure, heart failure, diabetes, or bleeding, liver, or kidney problems; plan to have any surgery or a dental procedure; or are pregnant, plan to become pregnant, or are breastfeeding.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your healthcare provider uses. Depending on your condition and medical history, your healthcare provider may prescribe a different regimen. Do not change the dosage or stop taking your medication without your healthcare provider's approval.

    Adults: Your healthcare provider will prescribe the appropriate dose for you based on your condition, and will adjust your dose as needed.

    Your Coumadin dose may need to be adjusted or stopped for a short time before you have any surgery or dental procedures, as instructed by your healthcare provider.

  • How should I take this medication?

    Take Coumadin exactly as prescribed by your healthcare provider. Do not change your dose or stop taking Coumadin without first talking to your healthcare provider.

  • What should I avoid while taking this medication?

    Do not miss any scheduled follow-up appointments with your healthcare provider.

    Do not engage in any activity or sport that may cause a serious injury.

  • What are the possible food and drug interactions associated with this medication?

    If Coumadin is taken with certain other drugs, the effects of either could be increased, decreased, or altered. Coumadin may interact with numerous medications. Therefore, it is very important that you tell your healthcare provider about any other medications you are taking.

    Some foods and beverages that contain vitamin K can interact with Coumadin and affect your treatment dose. Do not eat large amounts of leafy, green vegetables or certain vegetable oils, as they contain vitamin K. Too much vitamin K can lower the effect of Coumadin.

    Eat a normal, balanced diet while you are taking Coumadin and talk to your healthcare provider before making any changes to your diet.

  • May I receive this medication if I am pregnant or breastfeeding?

    Do not take Coumadin during pregnancy unless your healthcare provider instructs you to do so. Tell your healthcare provider immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of this medication?

    Coumadin should be taken under special circumstances determined by your healthcare provider. If you miss your scheduled dose, contact your healthcare provider or pharmacist for advice.

  • How should I store this medication?

    Store at room temperature. Protect from light and moisture.

Meet the Pharmacists

I'm Shereen A. Gharbia, PharmD. Welcome to PDR Health!

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