Coumadin (warfarin)

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Brand Name

Coumadin {Bristol-Myers Squibb}

Generic Name

warfarin, pronounced WAR far in

What is Coumadin? Coumadin is a medication that is known as a blood thinner, or an anticoagulant. By taking Coumadin you can reduce the formation of blood clots by blocking the formation of certain clotting factors in your body. Coumadin can help to prevent heart attacks, strokes, and blood clots in your veins and arteries. Coumadin may also be prescribed for purposes not listed in this medication guide.


Key Facts About Coumadin

Coumadin is in a class of medications called anticoagulants, or blood thinners. Because Coumadin can cause you to bleed more easily you should be cautious when taking this medication.

You may have a serious reaction to Coumadin if you take it with another medication. It is very important for you to tell your doctor about all of the drugs you take, including over-the-counter medicines and herbal products. There are many medications which may increase your risk of stomach bleeding, especially if they are medications for pain, arthritis, fever, or swelling.

Never double dose on products which contain Coumadin, warfarin or coumarin.

Your doctor may have prescribed Coumadin to help you reduce your risk of heart attack, stroke, and other heart complications, especially if you have diabetes, heart disease, or other risk factors. Coumadin may also be prescribed for purposes not listed in this medication guide.

Coumadin is in FDA pregnancy category X. We know that Coumadin can cause birth defects or fatal bleeding in an unborn baby. You should not use Coumadin if you are pregnant. Tell your doctor right away if you become pregnant while you are being treated with Coumadin. Coumadin may pass into breast milk and cause bleeding problems in a nursing baby, so should not use Coumadin without telling your doctor if you are breast-feeding.

Drinking alcohol may increase certain side effects of Coumadin, so you should not drink alcohol while taking Coumadin.

Be aware of dietary issues when taking Coumadin. You should not eat large amounts of foods that are high in vitamin K, like liver, leafy green vegetables or vegetable oils. A high intake of vitamin K may make Coumadin less effective. You should try to avoid eating cranberries, drinking cranberry juice, or taking cranberry herbal products, as well as herbal teas which contain tonka beans, sweet clover, or sweet woodruff. Talk to your doctor about any concerns regarding dietary restrictions that you may have.


Before You Take Coumadin

If you are allergic to warfarin you should not take Coumadin.

You should not take Coumadin if you have hemophilia or any bleeding disorder that is inherited or caused by disease, a blood cell disorder like anemia or a low level of platelets in your blood.

Tell your doctor if you have blood in your urine or stools, or if you have been coughing up blood.

If you have an infection of the lining of your heart called bacterial endocarditis, intestinal bleeding or a stomach ulcer, or a recent head injury, aneurysm, or bleeding in the brain you may not be a candidate to take Coumadin.

Tell your doctor if you have recently had or plan to have any type of surgery in the near future, especially brain, spine, or eye surgery, or if you will undergo a spinal tap or receive spinal anesthesia (an epidural).

If you have psychiatric problems, dementia, alcoholism or similar problems you should talk to your doctor before taking Coumadin.

Coumadin may cause you to bleed more easily, especially if you have a history of bleeding problems, kidney disease, high blood pressure, severe heart disease; cancer; a recent surgery or medical emergency, any disease which affects the blood vessels in your brain or a history of stomach or intestinal bleeding. Talk to your doctor if you feel that any of these concerns apply to your situation.

If you are 65 or older, or if you are severely ill or debilitated your doctor may adjust your dose or require you to take certain tests for conditions such as liver disease, celiac sprue (an intestinal disorder), diabetes, overactive thyroid, or congestive heart failure.

Inform your doctor if you have a connective tissue disorder like Marfan Syndrome, Sjogren syndrome, scleroderma, lupus or rheumatoid arthritis.

Before starting treatment with Coumadin you should tell your doctor if you have ever had low blood platelets after receiving heparin.


Coumadin Drug Interactions

You should inform your doctor if you are taking any of the following:

  • aspirin
  • Colace (docusate)
  • Coreg (carvedilol)
  • digoxin
  • furosemide
  • Lasix (furosemide)
  • levothyroxine
  • Lipitor (atorvastatin)
  • lisinopril
  • metformin
  • metoprolol
  • multivitamin
  • omeprazole
  • pain, arthritis, fever, or swelling medications like acetaminophen (Tylenol), celecoxib (Celebrex), ibuprofen (Advil, Motrin), diclofenac (Cataflam, Voltaren), indomethacin (Indocin), naproxen (Aleve, Naprosyn) and piroxicam (Feldene). These medications may affect blood clotting and increase your risk of stomach bleeding.
  • potassium chloride
  • prednisone
  • Zocor (simvastatin)
  • Synthroid (levothyroxine)
  • Tylenol (acetaminophen)
  • Vitamin D3 (cholecalciferol)
  • Zocor (simvastatin)
  • Coumadin may also interact with certain herbal products, which can increase your risk of bleeding. Do not use any of these products without consuting with your doctor first:
  • bromelains
  • coenzyme Q10
  • cranberry
  • danshen
  • dong quai
  • garlic
  • ginkgo biloba
  • ginseng
  • St. John’s wort

Other drugs you take that are not listed may interact with Coumadin. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Coumadin

Coumadin is usually prescribed as a medication to take once daily, with or without food. You should take Coumadin exactly as it is prescribed by your doctor. Your doctor may change your dose to make sure you get the best results from Coumadin. You should follow the instructions on your prescription label and not take Coumadin for longer than recommended by your doctor, or in larger or smaller doses.

You should take Coumadin at the same time every day.

Coumadin may be taken with or without food.

Maintain regular visits with your doctor and tell him or her at once if you have any illness with diarrhea, fever, chills, body aches, or flu symptoms.

You should not diet while taking Coumadin. Let your doctor know if you experience any unintentional weight changes.

Carry medical alert ID card stating that you take Coumadin, and be sure to let any doctor, dentist, surgeon, or other medical care provider you see that you are taking this drug. If you need antibiotic treatment, surgery, dental work, a spinal tap, or a spinal anesthesia (epidural) you may need to stop taking Coumadin for a short time. Your doctor will let you know when you can resume taking Coumadin.

Coumadin needs to be stored at room temperature, and away from light, moisture and heat.

If you miss a dose of Coumadin you should attempt to take the missed dose as soon as you remember. However, if it is almost time for your next scheduled dose do not take the missed dose in addition to your regular dose.


Coumadin Side Effects

If you experience any of the following adverse effects you should stop taking Coumadin and seek emergency medical help immediately;

  • allergic reaction signs, like breathing difficulties, hives and swelling of your face, lips, throat or tongue
  • black or bloody stools
  • bleeding from wounds or needle injections that will not stop
  • blood in your urine
  • coughing up blood
  • easy bruising or purple or red pinpoint spots under your skin
  • illness with diarrhea, fever, chills, body aches, or flu symptoms
  • jaundice or yellowing of your eyes and skin
  • numbness or muscle weakness
  • pain in your stomach, back or sides
  • pain and swelling with hot or cold feelings, skin changes, or discoloration anywhere on your body
  • pale skin and a light-headed feeling with shortness of breath, a rapid heart rate and trouble concentrating;
  • sudden and severe leg or foot pain, with a foot ulcer, purple toes or purple fingers
  • sudden headache with dizziness and weakness;
  • unusual bleeding from your nose, mouth, vagina, or rectum
  • urine which is dark
  • urinating less than usual or not at all
  • vomit that looks like coffee grounds

Less serious side effects of Coumadin may include:

  • altered sense of taste
  • bloating
  • gas
  • mild stomach pain
  • nausea
  • vomiting

It should be noted that this is not a complete list of possible side effects of Coumadin. You should contact your physician for a complete list and medical advice regarding these effects.


Coumadin Description and Dosing

Coumadin is available in following tablet strengths:

1mg, which is pink

2mg, which is lavender

2-1/2mg, which is green

3mg, which is tan

4mg, which is blue

5mg, which is peach

6mg, which is teal

7-1/2mg, which is yellow

10mg, which is white

All tablets are single scored, with the mg number superimposed on one side e and inscribed with “Coumadin” and with the opposite side plain.

Coumadin is also available for injection in a vial containing 5mg of lyophilized powder.

Coumadin is dosed based on individual conditions and situations. You should consult your doctor for specific dosing pertaining to you. Do not attempt to alter or change your dose without your physician’s consent.

If you suspect that you have overdosed with Coumadin you should seek emergency help immediately.


Ingredients in Coumadin

The primary active ingredient in Coumadin is warfarin sodium. All strengths of the tablets contain lactose, starch, and magnesium stearate. Individual dosages also include the following inactive ingredients:

1mg- D&C Red No. 6 Barium Lake

2mg- FD&C Blue No. 2 Aluminum Lake and FD&C Red No. 40 Aluminum Lake

2-1/2mg- D&C Yellow No. 10 Aluminum Lake and FD&C Blue No. 1 Aluminum Lake

3mg- FD&C Yellow No. 6 Aluminum Lake, FD&C Blue No. 2 Aluminum Lake, and FD&C Red No. 40 Aluminum Lake

4mg- FD&C Blue No. 1 Aluminum Lake

5mg- FD&C Yellow No. 6 Aluminum Lake

6mg- FD&C Yellow No. 6 Aluminum Lake and FD&C Blue No. 1 Aluminum Lake

7-1/2mg-D&C Yellow No. 10 Aluminum Lake and FD&C Yellow No. 6 Aluminum Lake

10mg is Dye-free

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

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