Direct and indirect anticoagulants

Almost all patients suffering from heart disease, needs to take special medications, blood thinners. All of these drugs can be divided into 2 main types: direct-acting anticoagulants and vitamin K antagonists (indirect action). How to find out what the difference between these two subspecies and what is the mechanism of their effects on the body?

Features of application of indirect anticoagulants

The indirect anticoagulants interfere with the synthesis of coagulation factors in the liver (prothrombin and prokonvertina). Their effect is seen in 8-12 hours after administration and lasts from several days to two weeks. The most important advantage of these drugs is that they have a cumulative effect. Antagonists of vitamin K (another name for indirect anticoagulants) more than 50 years are used for primary and secondary prevention of thromboembolism. It is vitamin K is an essential part of the coagulation process.

The advantages and disadvantages of anticoagulant drugs with direct action

For the last 6 years in the pharmaceutical market, a new direct anticoagulants. They are an alternative to vitamin K antagonists for the treatment of thromboembolism and prevention of thrombosis. Direct oral anticoagulants (PPA) are a more effective and safe analogue of vitamin K antagonists

For more effective mechanisms of direct anticoagulants include decontamination of blood platelets and decrease blood clotting. The half-life of this group of drugs is 7-14 hours, the time of occurrence of therapeutic effect varies from one to four hours. Direct anticoagulants are accumulated in the liver with the formation of active metabolites and excreted in the urine.

Also used as anticoagulants two types of heparins – non-factional (NFG) and low molecular weight (LMWH). Miscorrection heparin is used for prevention and mild treatment of thrombosis for several decades. Disadvantages of NFG is that it has a variable anticoagulant effect, as well as limited bioavailability. Low molecular weight heparin is prepared from miscorrection by depolymerization.

Low molecular weight heparin has a specific molecular weight distribution that determines its anticoagulant activity and duration of action. The advantage of LMWH is that it is easy to calculate the required dosage and not be afraid of severe side effects. For these reasons, namely the low-molecular subspecies of heparin is used in most hospitals in the world.