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WARFARIN (WAR far in) is an anticoagulant. It is used to treat or prevent clots in the veins, arteries, lungs, or heart.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
They need to know if you have any of these conditions:
high blood pressure
history of bleeding in the gastrointestinal tract
history of stroke or other brain injury or disease
kidney or liver disease
protein C deficiency
protein S deficiency
psychosis or dementia
recent injury, recent or planned surgery or procedure
an unusual or allergic reaction to warfarin, other medicines, foods, dyes, or preservatives
pregnant or trying to get pregnant
Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. You can take this medicine with or without food. Take your medicine at the same time each day. Do not take it more often than directed. Do not stop taking except on the advice of your doctor or health care professional.
A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
It is important not to miss a dose. If you miss a dose, call your healthcare provider. Take the dose as soon as possible on the same day. If it is almost time for your next dose, take only that dose. Do not take double or extra doses to make up for a missed dose.
Do not take this medicine with any of the following medications:
agents that prevent or dissolve blood clots
aspirin or other salicylates
St. John's Wort
red yeast rice
This medicine may also interact with the following medications:
agents that lower cholesterol
antibiotics or medicines for treating bacterial, fungal or viral infections
barbiturate medicines for inducing sleep or treating seizures
certain medicines for diabetes
certain medicines for heart rhythm problems
certain medicines for high blood pressure
female hormones, including contraceptive or birth control pills
herbal or dietary products like cranberry, garlic, ginkgo, ginseng, green tea, or kava kava
influenza virus vaccine
medicines for mental depression or psychosis
medicines for some types of cancer
medicines for stomach problems
NSAIDs, medicines for pain and inflammation, like ibuprofen or naproxen
seizure or epilepsy medicine like carbamazepine, phenytoin, and valproic acid
steroids like cortisone and prednisone
vitamin c, vitamin e, and vitamin K
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
Visit your doctor or health care professional for regular checks on your progress. 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.
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. 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, brussels 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.
Side effects that you should report to your doctor or health care professional as soon as possible:
back or stomach pain
chest pain or fast or irregular heartbeat
difficulty breathing or talking, wheezing
fever or chills
heavy menstrual bleeding or vaginal bleeding
painful, blue, or purple toes
painful, prolonged erection
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
skin rash, itching or skin damage
unusual swelling or sudden weight gain
unusually weak or tired
yellowing of skin or eyes
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
unusual hair loss
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Keep out of the reach of children.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light. Throw away any unused medicine after the expiration date.
blood disease, bleeding disorders, hemorrhage, hemophilia or aneurysm
bowel disease, diverticulitis, or ulcers
heart valve infection
older than 65 years
recent surgery or injury
This medicine is given by infusion into a vein. It is given by a health care professional in a hospital or clinic setting.
This does not apply.
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.
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.
allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
prolonged bleeding from cuts
yellowing of the eyes or skin
This drug is given in a hospital or clinic and will not be stored at home.