3-rx.comCustomer Support
HomeAbout UsFAQContactHelp
News Center
Health Centers
Medical Encyclopedia
Drugs & Medications
Diseases & Conditions
Medical Symptoms
Med. Tests & Exams
Surgery & Procedures
Injuries & Wounds
Diet & Nutrition
Special Topics

\"$alt_text\"');"); } else { echo"\"$alt_text\""; } ?>

You are here : 3-RX.com > Drugs & Medications > Quick Drug Information (DrugNotes) > Warfarin (Oral)

Warfarin (By Mouth)

Warfarin (WAR-far-in)

Treats or prevents blood clots. This medicine is a blood thinner (anticoagulant).

Brand Name(s):

Coumadin, Jantoven
There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have had an allergic reaction to warfarin or if you are pregnant. You should not use this medicine if you have had recent surgery, if you have certain heart problems, or if you have a condition that may cause uncontrolled bleeding (such as a stomach ulcer or hemophilia). Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using the medicine several days or weeks before having surgery or medical tests.

How to Use This Medicine:


  • Your doctor will tell you how much of this medicine to take and how often. Do not take more medicine or take it more often than your doctor tells you to.

If a dose is missed:

  • If you miss a dose or forget to take your medicine, take it as soon as you can. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose.
  • Do not use extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine:

  • Store the medicine at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine away from children and never share your medicine with anyone.
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, including nonprescription (over-the-counter) medicines and herbal products, that you should not use while you are taking warfarin. Make sure your doctor knows about ALL other medicines you are using.
  • Eating certain foods while you are using warfarin will change the way the medicine works. Foods that contain vitamin K (such as lettuce, spinach, broccoli, cabbage, cauliflower, or liver) may make the medicine less effective in preventing blood clots. Carefully follow your doctor's instructions about any special diet.
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 a stomach ulcer, liver disease, kidney disease, high blood pressure, or any other medical problems.
  • Your doctor will need to check your blood or urine at regular visits while you are using this medicine. Be sure to keep all appointments.
  • You may bleed 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.
  • Carry an ID card or wear a medical alert bracelet to let any emergency caregivers know that you are using warfarin.
Possible Side Effects While Using This Medicine:

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

  • Bleeding from your gums or nose, bruising easily, coughing up blood
  • Blood in your urine or stools
  • Decrease in how much or how often you urinate
  • Fever, chills, sore throat, cough
  • Heavy menstrual bleeding, or bleeding from cuts or wounds that does not stop
  • Purple discoloration of your toes or the soles of your feet
  • Swelling in your hands, ankles, or feet
  • Yellow skin or eyes

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

  • Diarrhea
  • Hair loss
  • Stomach pain or cramping
If you notice other side effects that you think are caused by this medicine, tell your doctor.

\"$alt_text\"');"); } else { echo"\"$alt_text\""; } ?>

Home | About Us | FAQ | Contact | Advertising Policy | Privacy Policy | Bookmark Site