Anticoagulants are a class of drugs that help prevent blood clots. They're often referred to as "blood thinners," although they don't actually thin the blood. Instead, they work by interrupting the process involved in the formation of blood clots.

There are several types of anticoagulants, each working in different ways:

1. Warfarin (Coumadin): Warfarin interferes with vitamin K, which is needed for the production of clotting factors. The effectiveness of warfarin can be influenced by diet and other medications, so it requires regular blood tests to monitor its effect.
2. Heparin and Low Molecular Weight Heparin (LMWH): Heparin works by binding to antithrombin, a substance that inhibits several clotting factors. LMWH is a form of heparin that has a more predictable response and doesn't require monitoring as frequently.
3. Direct Oral Anticoagulants (DOACs): These include drugs like dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis), and edoxaban (Savaysa). DOACs directly inhibit specific clotting factors (thrombin or Factor Xa) and have the advantage of requiring less monitoring than warfarin.

Anticoagulants are used in various conditions where there's a high risk of blood clots, such as atrial fibrillation, deep vein thrombosis (DVT), pulmonary embolism (PE), and in some cases after surgeries like hip or knee replacements. The choice of anticoagulant depends on the specific medical condition, patient characteristics, and the risk of bleeding.

It's important for people taking anticoagulants to be aware of their potential side effects, especially the increased risk of bleeding. Regular monitoring and following doctor's instructions regarding diet and other medications are crucial for safe and effective use of these drugs.