Warfarin is a class of anticoagulant drug; variants include warfarin potassium (trade name Athrombin-K) and warfarin sodium (trade names Coumadin and Panwarfin).

Like other anticoagulant drugs, it may be prescribed to reduce the risk of blood clots in patients who have had or are at risk of having strokes. And, like other anticoagulant drugs, there can be negative side effects including the risk of internal bleeding.

Warfarin poisoning can occur due to accidental overdose or by cumulative buildup of the drug in the body over a long period of treatment. It can cause bleeding of the gums, nose and skin, as well as blood in the feces and urine.

Further Reading:

The Mayo Health Clinic (http://www.mayohealth.org) maintains a current list of information about drugs approved for use in the US.

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