Aspirin in NOT a blood thinner. It is an antiplatelet medication. Platelets are blood cells that stick together to form a clot and stop bleeding. Aspirin works by inhibiting or stopping the production of thromboxane — a chemical that a platelet releases calling for other platelets in the area to help out, stick together and plug up the bleeding cut/injury. If thromboxane cannot be released, then the other platelets don’t receive the message to clump together and form a platelet plug and the cut continues to bleed. Obviously with time, the bleeding will stop because the plug will eventually form but it just takes much longer.
Anticoagulants or blood thinners affect proteins (also known as cofactors) in the liver. These cofactors are essential for the blood to clot. In order for these cofactors to be made in the liver, the liver needs vitamin K. Anticoagulants such as warfarin (i.e. Coumadin) prevent the liver from using the vitamin K in food, thereby preventing the cofactors from being created. This decreases the ability of the blood to clot. Since warfarin works against vitamin K, patients taking warfarin should use moderation in eating foods rich in vitamin K such as green leafy vegetables. Those who normally have a vitamin K rich diet should consider talking to their doctor or a dietician about what foods to eat since too much vitamin K will make the blood levels of warfarin low. Since warfarin takes several days to reach a therapeutic level in the blood, warfarin requires weekly or bi-weekly blood tests. Newer anticoagulants known as Direct Oral Anticoagulants (DOACs) do NOT affect vitamin K and instead directly inhibit the blood from clotting. As a results, DOACs do not have diet restrictions and do not require weekly blood tests.
IMPORTANT POINT: Anticoagulants do NOT affect platelet function and so they are not the same as antiplatelet agents.
Aspirin and anticoagulants may SEEM the same because if you cut yourself while on either of them, the bleeding takes a while to stop. However, they are NOT the same, and it should not be assumed that taking aspirin offers the same protection as an anticoagulant. There are times when a patient may be taken off an anticoagulant and placed on aspirin instead but this must be done under the supervision of a physician and not done based on what people read on the internet or social media groups.