What to Watch for While On Warfarin

Bleeding
Warfarin decreases the chance of blood clots forming, which means that you may bleed more easily. You can reduce the chance of bleeding side effects by:

  • Taking your warfarin exactly as directed
  • Getting your INR blood test completed regularly
  • Following the guidelines in your booklet (also listed on this page)
  • Being a good observer for any signs of possible bleeding 

Possible Signs of Bleeding
Some signs of bleeding are very obvious and some are not. However, they are all important for your doctor to know about. If you ever have any questions about side effects, don’t hesitate to call your doctor or the Anticoagulation Clinic. If you do experience bleeding side effects, call your doctor right away.

Obvious Signs

  • Nose bleeds or bleeding from a cut lasting 10 minutes or longer
  • Bleeding from your gums
  • Vomiting or coughing up blood
  • Unusually easy or unexplained bruising
  • Increased menstrual flow or unexpected vaginal bleeding

Less Obvious Signs

  • Red- or black-colored stools
  • Red or orange urine
  • Prolonged or severe headaches
  • Pale skin
  • Constant tiredness

Clotting
Your medical condition puts you at an increased risk of forming a clot. Therefore, if your INR becomes too low, there is an increased chance that a clot could form. These clots can remain where they form, or they may travel through the bloodstream and lodge in another part of the body. You can reduce your risk of a clot forming by following the same steps listed on the previous page. If you have any questions regarding the signs of a clot or stroke, don’t hesitate to call your doctor or the Anticoagulation Clinic. If you experience any of the signs listed below, call your doctor immediately.

Signs of a Stroke

  • Numbness or weakness of the body
  • Difficulty speaking (slurred speech)
  • Confusion
  • Unexplained dizzy spells
  • Severe headache

Signs of a Clot

  • Pain or tenderness in your legs or arms
  • Swelling and/or warmth of your legs or arms
  • Changes in skin coloration on your legs or arms (usually red or purple)
  • Shortness of breath or difficulty breathing
  • Chest pain when breathing deeply