Approved in 1954 for human use, Warfarin (brand name Coumadin) is an anticoagulant, used to treat embolism and thrombosis in a number of medical disorders. Coumadin decrease blood coagulation by inhibiting an enzyme called ‘epoxide reductase,’ thereby interfares with vitamin K metabolism. The medicine is prescribed for therapeutic treatment of persons with increased risk of thrombosis or those already suffered from formation of thrombus (blood clot) to prevent further blood clots and resulting episodes. It is interesting to note that US President Dwight Eisenhower was administered warfarin after a heart attack in 1955.

Benefits of Coumadin as anticoagulant:

The drug is indicated for use in cases of atrial fibrillation, deep venous thrombosis, pulmonary embolism, antiphospholipid syndrome and at times after myocardial infarction. Coudmadin is also indicated where artificial valve is implanted in the heart. To reduce death risk, the drug is beneficial in preventing recurrent myocardial infarction, stroke or systemic embolization after myocardial infarction. Coumadin is also preferred in patients with history of prior ischemic stroke, transient ischemic attack, having severely impaired left ventricular systolic function and congestive heart failure.

Warfarin has a slower action than Heparin, a common anticoagulant. But warfarin can be taken orally while heparin must be given through injection. Warfarin need be given only once a day and has a long half life making it effective even several days after the drug is withdrawn. Since anticoagulant action of Coumadin is slow, heparin is initially administered along with Coumadin for 4-5 days so that heparin may provide rapid initial anticoagulation allowing Coumadin to built up anticoagulation response in the meanwhile(as is confirmed by PT/INR tests) where after heparin is withdrawn and therapy continues with Coumadin.

Doses and administration of Coumadin is highly patient specific. Therefore Coumadin is available in strengths of 1mg to 10mg in a total of 9 configurations. The tablets are scored on one side so that the doses can further be halved. Intravenous injection is also available in 5mg vials. Al this makes Coumadin a very patient friendly drug with accurate dosing.

Side Effects of Coumadin (Warfarin):

As a direct consequence of anticoagulant property, Coumadin may cause severe bleeding (hemorrhage) from any tissue or organs and such hemorrhage may not always be correlated with overdosing. The diffused symptoms of hemorrhage may be pains in chest, muscle, abdomen, joints, including dizziness, breathing shortness, headache etc. However if bleeding is confirmed within therapeutic range of PT (prothrombin time) and/or INR (International Normalized Ratio) test results, investigations may be warranted for any pre-existing lesions like tumor, ulcer etc

Less frequent (