The objective of this review is to raise awareness among medical practitioners and patients. Warfarin is still the most frequently used anticoagulant worldwide in the treatment regimen of mechanical heart valves and any condition that could lead to the formation of blood clots in the blood vessels. This drug is particularly used as a prophylaxis regimen for atrial fibrillation and another use of warfarin to prevent thromboembolism that will lead to Stroke is post artificial heart valve replacement. Furthermore, the mechanism of warfarin helps us see clearly how it inhibits further coagulation of blood. The active direct thrombin and Xa inhibitor drugs have been introduced for the treatment and prevention of venous and arterial thrombosis and such drugs have a much broader therapeutic window than warfarin. Warfarin is seen to cause many side effects such as bleeding. Previous studies indicated that the risk a bleeding in warfarin use is higher than any other anticoagulant use such as heparin and other non-vitamin k dependent drugs. More research is needed to stop promoting the use of warfarin in the society.