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Warfarin Sodium Solution for injection

It is used to treat or prevent clots in the veins, arteries, lungs, or heart

Generic Name: warfarin  |  Brand Name: Coumadin

Brand Names: Warfarin Sodium, Coumadin, Jantoven

There is an FDA Alert for this drug. Click here to view it.

What is this medicine?

WARFARIN (WAR far in) is an anticoagulant. It is used to treat or prevent clots in the veins, arteries, lungs, or heart.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • alcoholism
  • anemia
  • blood disease, bleeding disorders, hemorrhage, hemophilia or aneurysm
  • bowel disease, diverticulitis, or ulcers
  • cancer
  • diabetes
  • heart disease
  • heart valve infection
  • high blood pressure
  • history of bleeding in the gastrointestinal tract
  • history of stroke or other brain injury or disease
  • kidney disease
  • liver disease
  • older than 65 years
  • protein C deficiency
  • protein S deficiency
  • psychosis or dementia
  • recent surgery or injury
  • an unusual or allergic reaction to warfarin, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

This medicine is given by infusion into a vein. It is given by a health care professional in a hospital or clinic setting.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

What if I miss a dose?

This does not apply.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
  • agents that prevent or dissolve blood clots
  • aspirin or other salicylates
  • danshen
  • dextrothyroxine
  • mifepristone
  • St. John's Wort
  • red yeast rice

This medicine may also interact with the following medications:

  • acetaminophen
  • agents that lower cholesterol
  • alcohol
  • allopurinol
  • amiodarone
  • antibiotics or medicines for treating bacterial, fungal or viral infections
  • azathioprine
  • barbiturate medicines for inducing sleep or treating seizures
  • certain medicines for diabetes
  • certain medicines for heart rhythm problems
  • certain medicines for high blood pressure
  • chloral hydrate
  • cisapride
  • disulfiram
  • female hormones, including contraceptive or birth control pills
  • general anesthetics
  • herbal or dietary products like cranberry, garlic, ginkgo, ginseng, green tea, or kava kava
  • influenza virus vaccine
  • male hormones
  • medicines for mental depression or psychosis
  • medicines for some types of cancer
  • medicines for stomach problems
  • methylphenidate
  • NSAIDs, medicines for pain and inflammation, like ibuprofen or naproxen
  • propoxyphene
  • quinidine, quinine
  • raloxifene
  • seizure or epilepsy medicine like carbamazepine, phenytoin, and valproic acid
  • steroids like cortisone and prednisone
  • tamoxifen
  • thyroid medicine
  • tramadol
  • vitamin c, vitamin e, and vitamin K
  • zafirlukast
  • zileuton

What should I watch for while using this medicine?

Your condition will be monitored carefully while you are receiving this medicine.

You will need to have your blood checked regularly to make sure you are getting the right dose of this medicine. When you first start taking this medicine, these tests are done often. Once the correct dose is determined and you take your medicine properly, these tests can be done less often.

While you are taking this medicine, carry an identification card with your name, the name and dose of medicine(s) being used, and the name and phone number of your doctor or health care professional or person to contact in an emergency.

You should discuss your diet with your doctor or health care professional. Do not make major changes in your diet. Many foods contain high amounts of vitamin K, which can interfere with the effect of this medicine. Your doctor or health care professional may want you to limit your intake of foods that contain vitamin K. Some foods that have moderate to high amounts of vitamin K are green leafy vegetables like beet greens, collard greens, endive, kale, mustard greens, spinach, turnip greens, watercress, and certain lettuces like green leaf or romaine. Some other foods that have high to moderate amounts of vitamin K are asparagus, black eye peas, broccoli, brussel sprouts, cabbage, cucumber with peel, okra, peas, parsley, and green onions.

This medicine can cause birth defects or bleeding in an unborn child. Women of childbearing age should use effective birth control while taking this medicine. If a woman becomes pregnant while taking this medicine, she should discuss the potential risks and her options with her health care professional.

Avoid sports and activities that might cause injury while you are using this medicine. Severe falls or injuries can cause unseen bleeding. Be careful when using sharp tools or knives. Consider using an electric razor. Take special care brushing or flossing your teeth. Report any injuries, bruising, or red spots on the skin to your doctor or health care professional.

If you have an illness that causes vomiting, diarrhea, or fever for more than a few days, contact your doctor. Also check with your doctor if you are unable to eat for several days. These problems can change the effect of this medicine.

Even after you stop taking this medicine, it takes several days before your body recovers its normal ability to clot blood. Ask your doctor or health care professional how long you need to be careful. If you are going to have surgery or dental work, tell your doctor or health care professional that you have been taking this medicine.


Last Updated: April 18, 2012
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