Warfarin is often compared to Heparin (another strong anticoagulant) but their methods of action are very different. Heparin works as an anticoagulant by inactivating thrombin and factor X through antithrombin-dependent mechanism. The binding with antithrombin occurs through antithrombin dependent mechanism which is on around a third of heparin molecules. Heparin is also different in its fast acting results with its average half life being less than an hour. Heparin is given intravenously or via subcutaneous injection but cannot given via the oral route. Often these two anticoagulant drugs are used together to produce the ideal effect. Heparin is started for patients that need a quick remedy but then stopped when warfarin takes effect …show more content…
The most common side effect of warfarin and other anticoagulants is bleeding. Some common examples include bleeding from gums when brushing teeth, heavier than normal menstrual bleeding or bleeding between periods, blood found in urine. The risk for bleeding increases with patients over the age of 65 and in patients with hypertension, serious heart disease, renal disease, cocomitant drugs, and with a long duration of warfarin therapy.
The FDA has issued a black box warning on warfarin because of the chance it could lead to severe or even fatal bleeding. The black box also recommends regular monitoring of INR.
Another common side effect also called Coumadin-Induced skin necrosis (CISN) is the condition in which the subcutaneous tissue dies (necrosis) because of a protein C deficiency associated with anti-vitamin K anticoagulants. This is a fairly rare side effect but can be very serious. It is associated with large loading doses and is most commonly found in obese women. The first signs are redness and pain and would typically occur between three to ten days after starting the drug. The common sites for necrosis are areas with subcutaneous fat like breasts, thighs, and buttox. The pain and redness may form into large bloody bullae and a slow healing eschar