warfarin

Brand names: Warfarin Sodium

# Warfarin: What You Need to Know Warfarin is a blood thinner medication that helps prevent blood clots from forming in your body. Doctors prescribe it to patients who have had a stroke, heart attack, or certain heart conditions, or who have blood clots in their legs or lungs. By making your blood less likely to clot, warfarin helps reduce the chance that dangerous clots will block blood vessels and cause serious health problems. However, warfarin is a powerful medicine that requires careful use and regular monitoring by your doctor. Because warfarin thins your blood, the biggest safety concern is bleeding. You need to be extra careful to avoid injuries, and you should tell your doctor right away if you notice unusual bruising, nosebleeds, or blood in your urine or stool. Many other medications can interact with warfarin and change how it works, including antibiotics, pain relievers, and herbal supplements, so always tell your doctor about everything you take. Your doctor will do regular blood tests to make sure warfarin is working properly for you. Never stop taking warfarin or change your dose without talking to your doctor first, as this could be dangerous.

Known Interactions

7 DRUG INTERACTIONS Concomitant use of drugs that increase bleeding risk, antibiotics, antifungals, botanical (herbal) products, and inhibitors and inducers of CYP2C9, 1A2, or 3A4. ( 7 ) Consult labeling of all concurrently used drugs for complete information about interactions with warfarin sodium or increased risks for bleeding. ( 7 ) 7.1 General Information Drugs may interact with warfarin sodium through pharmacodynamic or pharmacokinetic mechanisms. Pharmacodynamic mechanisms for drug interactions with warfarin sodium are synergism (impaired hemostasis, reduced clotting factor synthesis), competitive antagonism (vitamin K), and alteration of the physiologic control loop for vitamin K metabolism (hereditary resistance). Pharmacokinetic mechanisms for drug interactions with warfarin sodium are mainly enzyme induction, enzyme inhibition, and reduced plasma protein binding. It is important to note that some drugs may interact by more than one mechanism. More frequent INR monitoring sho

Source: FDA-approved drug labeling via openFDA

Most Reported Side Effects (FAERS)

  • INTERNATIONAL NORMALISED RATIO INCREASED10,373 reports
  • DYSPNOEA8,469 reports
  • DRUG INTERACTION6,314 reports
  • FATIGUE6,206 reports
  • NAUSEA5,974 reports
  • DIARRHOEA5,961 reports
  • DIZZINESS5,219 reports
  • DRUG INEFFECTIVE5,166 reports
  • FALL4,857 reports
  • DEATH4,768 reports

Source: FDA Adverse Event Reporting System (FAERS). Voluntary reports do not establish causation.

Check interactions with warfarin:

SafeCheck provides drug interaction information from FDA-approved product labeling (openFDA). This is for informational purposes only and is not medical advice. Always consult your healthcare provider before making medication decisions.