Anticoagulants or blood thinners as they are commonly known are effective in preventing blood clots in the human body. Blood clots are dangerous and can stop the flow of blood to important organs in the body such as the heart, brain or the lungs. Taken either orally or injected into the bloodstream, by people who have heart ailments, blood thinner drug treatments are helpful in averting major illnesses such as heart attacks or strokes in people.