What Is Warfarin Used For?
Certain types of blood clots, such as those in the veins, in the lungs, and in people with atrial fibrillation or artificial heart valves, can be treated and prevented with warfarin. The drug also can be administered after a heart attack to reduce the risk of death, repeat heart attacks, blood clots, or strokes. Healthcare providers may occasionally recommend "off-label" warfarin uses as well.
Warfarin sodium (Coumadin®, Jantoven®) is anticoagulant "blood thinner" medication used to prevent and treat blood clots. Specifically, warfarin is approved for the following uses:
- Preventing or treating blood clots in the veins (such as with deep vein thrombosis)
- Preventing or treating blood clots in the lungs (pulmonary embolism)
- Preventing or treating blood clots or related problems (such as strokes) in people with atrial fibrillation or artificial heart valves
- Reducing the risk of death, repeat heart attacks, blood clots, or strokes after a heart attack.
Warfarin has advantages and disadvantages. Advantages include painless oral dosing and low cost. Disadvantages include numerous food and drug interactions, the need for frequent monitoring (using blood tests), and a narrow range for both safety and effectiveness (taking too little increases the risk of blood clots, while taking too much increases the risk of dangerous internal bleeding). Warfarin is difficult to dose, and the cost of monitoring also must be taken into account.
In addition, warfarin is slow to start working. In fact, when a person first starts taking it, he or she actually may be at an increased risk for clots, since warfarin first decreases certain anticoagulant proteins in the body, before it starts working to prevent clots. As a result, in many cases, people will need to be on heparin or some other form of injectable or IV anticoagulant for a few days until warfarin starts working.