Warfarin (WAR-far-in)

Helps to prevent new blood clots from forming, and helps to keep existing blood clots from getting worse. This medicine is a blood thinner (anticoagulant).

Brand Name(s):

Coumadin

When This Medicine Should Not Be Used:

How to Use This Medicine:

Injectable

• A nurse or other trained health professional will give you this medicine.
• Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given through a needle placed in one of your veins.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• There are many other medicines that you should not use while you are using warfarin. These include many herbs, supplements, and over-the-counter (nonprescription) medicines. Ask your doctor before you use any other medicine, especially products that contain nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen, naproxen, Motrin®, Advil®, or Aleve®. Carefully check the labels of all other medicines you are using to be sure they do not contain NSAIDs.
• Carefully follow your doctor's instructions about any special diet. This medicine works best when you eat about the same amount of vitamin K in your food every day. Avoid big changes in how much vitamin K you eat. Some foods that have a high amount of vitamin K are broccoli, brussels sprouts, cabbage, and green leafy vegetables such as spinach and salad greens.
• Do not eat cranberry fruit or drink cranberry juice while you are using this medicine.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.
• Make sure your doctor knows if you are breastfeeding, or if you have liver disease, kidney disease, congestive heart failure, or high blood pressure. Tell your doctor if you have had any recent illnesses or infections, or a fall or other injuries. Make sure your doctor knows if you have a history of blood or circulation problems, diabetes, or any other medical problems.
• You may bleed and bruise more easily while you are using this medicine. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers. Avoid picking your nose. If you need to blow your nose, blow it gently.
• Carry an ID card or wear a medical alert bracelet so that during an emergency, health caregivers will know that you are using warfarin.
• Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery or medical tests.
• Your doctor will need to check your blood at regular visits while you are using this medicine. Be sure to keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
• Bleeding from your gums or nose, bruising easily, or coughing up blood.
• Decrease in how much or how often you urinate, or trouble urinating.
• Dizziness, lightheadedness, or trouble thinking clearly.
• Fever, chills, sore throat, or cough.
• Heavy menstrual bleeding, or bleeding from cuts or wounds that does not stop.
• Numbness, tingling, or weakness anywhere in your body, or problems with movement, swallowing, or speech.
• Pain, itching, burning, swelling, or a lump under your skin where the needle is placed.
• Purple discoloration of your toes or feet, or new pain in a leg, foot, or your toes.
• Red or dark brown urine, or red or black stools.
• Sudden or severe headache, or new pain in your abdomen (belly), flank (sides), or back.
• Swelling in your hands, ankles, or feet.
• Vomiting of blood or material that looks like coffee grounds.
• Yellowing of your skin or the whites of your eyes.

If you notice these less serious side effects, talk with your doctor:

• Headache, muscle or joint pains.
• Nausea, vomiting, diarrhea, or upset stomach.