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Warfarin injection

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.

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 side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

  • breathing problems

  • chest pain

  • dizziness

  • headache

  • heavy menstrual bleeding or vaginal bleeding

  • pain in the lower back or side

  • painful, blue or purple toes

  • painful skin ulcers that do not go away

  • signs and symptoms of bleeding such as bloody or black, tarry stools; red or dark-brown urine; spitting up blood or brown material that looks like coffee grounds; red spots on the skin; unusual bruising or bleeding from the eye, gums, or nose

  • stomach pain

  • unusually weak or tired

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • diarrhea

  • hair loss

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

  • conivaptan

  • disulfiram

  • female hormones, including contraceptive or birth control pills

  • general anesthetics

  • herbal or dietary products like 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 if I miss a dose?

This does not apply.

Where should I keep my medicine?

This drug is given in a hospital or clinic and will not be stored at home.

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

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular checks on your progress. You will need to have a blood test called a PT/INR regularly. The PT/INR blood test is done to make sure you are getting the right dose of this medicine. It is important to not miss your appointment for the blood tests. 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.

Notify your doctor or health care professional and seek emergency treatment if you develop breathing problems; changes in vision; chest pain; severe, sudden headache; pain, swelling, warmth in the leg; trouble speaking; sudden numbness or weakness of the face, arm or leg. These can be signs that your condition has gotten worse.

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.

Do not start taking or stop taking any medicines or over-the-counter medicines except on the advice of your doctor or health care professional.

You should discuss your diet with your doctor or health care professional. Do not make major changes in your diet. Vitamin K can affect how well this medicine works. Many foods contain vitamin K. It is important to eat a consistent amount of foods with vitamin K. Other foods with vitamin K that you should eat in consistent amounts are asparagus, basil, black eyed peas, broccoli, brussel sprouts, cabbage, green onions, green tea, parsley, green leafy vegetables like beet greens, collard greens, kale, spinach, turnip greens, or certain lettuces like green leaf or romaine.

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.

Author: StayWell Custom Communications
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