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Medications and Drugs

Brand Names: Coumadin, Jantoven

Generic Name: warfarin (Pronunciation: WAR far in)

What is warfarin (Coumadin, Jantoven)?

Warfarin is an anticoagulant (blood thinner). Warfarin reduces the formation of blood clots.

Warfarin is used to prevent heart attacks, strokes, and blood clots in veins and arteries.

Warfarin may also be used for purposes not listed in this medication guide.

Coumadin 1 mg

round, pink, imprinted with Dupont, COUMADIN 1

Coumadin 10 mg

round, white, imprinted with DuPont, COUMADIN 10

Coumadin 2 mg

round, lavender, imprinted with COUMADIN 2, DuPont

Coumadin 2.5 mg

round, green, imprinted with DuPont, COUMADIN 2 1/2

Coumadin 3 mg

round, beige, imprinted with DuPont, COUMADIN 3

Coumadin 4 mg

round, blue, imprinted with DuPont, COUMADIN 4

Coumadin 5 mg

round, peach, imprinted with DuPont, COUMADIN 5

Coumadin 6 mg

round, turquoise, imprinted with COUMADIN 6, DuPont

Coumadin 7.5 mg

round, yellow, imprinted with DuPont, COUMADIN 7 1/2

Warfarin 1 mg-TAR

oval, pink, imprinted with 1, WARFARIN TARO

Warfarin 10 mg-BAR

oval, white, imprinted with barr, 835 10

Warfarin 1mg-BAR

oval, pink, imprinted with barr, 831 1

Warfarin 2 mg-APH

square, lavender, imprinted with INV 310, 2

Warfarin 2 mg-BAR

oval, lavender, imprinted with barr, 869 2

Warfarin 2 mg-TAR

oval, lavender, imprinted with T32

Warfarin 2.5 mg-APH

square, green, imprinted with INV 311, 2.5

Warfarin 2.5 mg-BAR

oval, green, imprinted with barr, 832 2 1/2

Warfarin 2.5 mg-TAR

oval, green, imprinted with T33

Warfarin 3 mg-BAR

oval, tan, imprinted with barr, 925 3

Warfarin 3 mg-TAR

oval, beige, imprinted with 3, WARFARIN TARO

Warfarin 4 mg-BAR

oval, blue, imprinted with barr, 874 4

Warfarin 4 mg-TAR

oval, blue, imprinted with 4, WARFARIN TARO

Warfarin 5 mg-APH

square, peach, imprinted with INV 313, 5

Warfarin 5 mg-BAR

oval, peach, imprinted with barr, 833 5

Warfarin 5 mg-TAR

oval, peach, imprinted with T35

Warfarin 6 mg-BAR

oval, blue, imprinted with barr, 926 6

Warfarin 6 mg-TAR

oval, turquoise, imprinted with 6, WARFARIN TARO

Warfarin 7.5 mg-BAR

oval, yellow, imprinted with barr, 834 7 1/2

Warfarin 7.5 mg-TAR

oval, yellow, imprinted with 7 1-2, WARFARIN TARO

What are the possible side effects of warfarin (Coumadin, Jantoven)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using warfarin and call your doctor at once if you have a serious side effect such as:

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

Less serious side effects may include:

  • nausea, vomiting, mild stomach pain;
  • bloating, gas; or
  • altered sense of taste.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about warfarin (Coumadin, Jantoven)?

Follow your doctor's instructions about taking warfarin while you are pregnant. Warfarin can harm an unborn baby or cause birth defects. However, the benefits of preventing blood clots in certain women may outweigh any risks to the baby.

Never take a double dose of this medication.

You should not take warfarin if you have a bleeding or blood cell disorder, blood in your urine or stools, an infection of the lining of your heart, stomach bleeding, bleeding in the brain, recent or upcoming surgery, or if you need a spinal tap or spinal anesthesia (epidural).

Warfarin may cause you to bleed more easily, especially if you have: a history of bleeding problems, high blood pressure or severe heart disease, kidney or liver disease, cancer, surgery or a medical emergency, a disease affecting the blood vessels in your brain, a history of stomach or intestinal bleeding, if you are 65 or older, or if you are severely ill or debilitated.

Many drugs (including some over-the-counter medicines and herbal products) can cause serious medical problems or death if you take them with warfarin. It is very important to tell your doctor about all medicines you have recently used.

Ask your doctor before taking any medicine for pain, arthritis, fever, or swelling. These medicines may affect blood clotting and may also increase your risk of stomach bleeding.

Any doctor, dentist, surgeon, or other medical care provider who treats you should know that you are taking this medication.

Avoid making any changes in your diet without first talking to your doctor.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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