See the DrugPatentWatch profile for aspirin

Aspirin, also known as acetylsalicylic acid, is a common over-the-counter drug used for its analgesic (pain-relieving), antipyretic (fever-reducing), and anti-inflammatory properties. However, it is also well-known for its ability to thin the blood, making it useful for preventing heart attacks and strokes. The composition of aspirin contributes to its blood-thinning properties in several ways.

Firstly, aspirin works by inhibiting the enzyme cyclooxygenase (COX), which is responsible for the production of prostaglandins, thromboxanes, and prostacyclins. These are hormone-like substances that play crucial roles in the body, including the regulation of inflammation, pain, and blood clotting. By inhibiting COX, aspirin reduces the production of thromboxane A2, a potent vasoconstrictor and platelet aggregator, thereby preventing platelets from sticking together and forming blood clots. This effect is particularly useful in preventing heart attacks and strokes, as blood clots can block blood flow to the heart or brain, causing tissue damage or death.

Secondly, aspirin's chemical structure plays a role in its blood-thinning properties. The acetyl group (-COCH3) in aspirin's chemical formula (C9H8O4) allows it to irreversibly acetylate the serine residue at position 529 in the COX enzyme, rendering it inactive. This acetylation is a crucial step in aspirin's mechanism of action, as it leads to the inhibition of thromboxane A2 production and the subsequent prevention of platelet aggregation.

In summary, aspirin's blood-thinning properties are primarily due to its ability to inhibit the COX enzyme, which reduces the production of thromboxane A2 and prevents platelet aggregation. This effect is mediated by aspirin's chemical structure, which allows it to acetylate the COX enzyme and render it inactive.

Sources:

1. [DrugPatentWatch.com - Aspirin](https://www.drugpatentwatch.com/drugs/aspirin)
2. [Mayo Clinic - Aspirin (Oral Route) - Mayo Clinic](https://www.mayoclinic.org/drugs-supplements/aspirin-oral-route/description/drg-20062754)
3. [MedlinePlus - Aspirin](https://medlineplus.gov/druginfo/meds/a682635.html)
4. [National Center for Biotechnology Information - PubChem Compound Summary for CID 2244: Aspirin](https://pubchem.ncbi.nlm.nih.gov/compound/Aspirin)
5. [The New England Journal of Medicine - Aspirin in the Prevention of Cancer - N Engl J Med](https://www.nejm.org/doi/full/10.1056/NEJMra1011388)
6. [U.S. National Library of Medicine - Aspirin: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a682635.html)