Brief about Anticoagulants.
May 05, 2017
Anticoagulants or blood thinners are chemicals which reduce or prevent coagulation of blood and increases the clotting time. These chemicals are naturally present in blood eating animals like mosquitoes and leeches that allow the bite area to be unclotted to suck blood.
In diseases like Coronary artery disease, Atrial fibrillation, Ischemic stroke, Deep vein thrombosis, Pulmonary embolism, Restenosis from stents, Hypercoagulable conditions like Factor V Leiden, Myocardial infarction etc anticoagulants help in prevention of formation of clots and restrict its growth
- Novel oral anticoagulants or Non Vitamin K antagonist oral anticoagulants (NOACs) - they inhibits formation of clots but are not Vitamin K antagonists. They include rivaroxaban, apixaban, dabigatran etc. They have comparatively shorter half lives and rapid action than warfarin and are lot more expensive than them.
- Coumarins (vitamin K antagonists) - the most important medicine in this class is wafarin. It takes 42 to 72 hours for development of anti coagulation. Other medicines belonging to this class include phenindione, phenprocoumon, acenocoumarol, and atromentin.
- Heparin and derivative substances- Heparin is made from the intestines of pig. It acts by activating antithrombin III, which in turns prevents thrombin from clotting blood. Heparin is used both in-vivo and in-vitro for blood clotting.
- Low molecular weight heparin- it is a more processed form of heparin and is frequently used since has fewer side effects and it does not require monitoring of APTT coagulation parameters.
- Synthetic pentasaccharide inhibitors of factor Xa- Idraparinux, Fondaparinux
- Direct factor Xa inhibitors- apixaban, edoxaban, betrixaban, eribaxaban, letaxaban, darexaban, rivaroxaban etc.
- Direct thrombin inhibitors- ximelagatran, argatroban, lepirudin, hirudin, bivalirudin and dabigatran.
- Antithrombin protein therapeutics- it is obtained from human plasma
- Other types of anticoagulants- Batroxobin (from snake’s venom), Hementin (from Amazon leech Haementeria ghilianii), Vitamin E
- Elderly patients may be more susceptible to bleeding.
- Patients with recent surgeries, cerebral aneurysms have greater risk of bleeding
Disclaimer: The information given in this write-up is purely for educating the reader. It is not meant to be a substitute for any advice from a medical expert.