Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Jantoven increases your risk of bleeding, which can be severe or life-threatening. Call your doctor at once if you have any signs of bleeding such as:
sudden headache, feeling very weak or dizzy;
swelling, pain, unusual bruising;
bleeding gums, nosebleeds;
bleeding from wounds or needle injections that will not stop;
heavy menstrual periods or abnormal vaginal bleeding;
blood in your urine, bloody or tarry stools; or
coughing up blood or vomit that looks like coffee grounds.
Clots formed by Jantoven may block normal blood flow, which could lead to tissue death or amputation of the affected body part. Get medical help at once if you have:
pain, swelling, hot or cold feeling, skin changes, or discoloration anywhere on your body; or
sudden and severe leg or foot pain, foot ulcer, purple toes or fingers.
Bleeding is the most common side effect of warfarin.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Jantoven side effects (more detail)
