Antiplatelet agents inhibit the aggregation of platelets and erythrocytes, reduce their ability to adhere and adhere (adhesion) to the endothelium of blood vessels. By reducing the surface tension of erythrocyte membranes, they facilitate their deformation when passing through the capillaries and improve blood flow. Antiplatelet agents can not only prevent aggregation, but also cause disaggregation of already aggregated platelets.
They are used to prevent the formation of postoperative blood clots, in thrombophlebitis, retinal vascular thrombosis, cerebrovascular accidents, etc., as well as to prevent thromboembolic complications in coronary heart disease and myocardial infarction.
The inhibitory effect on the adhesion (aggregation) of platelets (and erythrocytes) is exerted to one degree or another by drugs of different pharmacological groups (organic nitrates, calcium channel blockers, purine derivatives, antihistamines, etc.). NSAIDs have a pronounced antiplatelet effect, of which acetylsalicylic acid is widely used for the prevention of thrombus formation.
Acetylsalicylic acid is currently the main representative of antiplatelet agents. It has an inhibitory effect on spontaneous and induced platelet aggregation and adhesion, on the release and activation of platelet factors 3 and 4. It has been shown that its antiaggregatory activity is closely related to the effect on PG biosynthesis, liberation and metabolism. It promotes the release of PGs by the vascular endothelium, incl. PGI2 (prostacyclin). The latter activates adenylate cyclase, reduces the content of ionized calcium in platelets – one of the three main mediators of aggregation, and also has a disaggregation activity. In addition, acetylsalicylic acid, suppressing the activity of cyclooxygenase, reduces the formation of thromboxane A in platelets2 – prostaglandin with the opposite type of activity (pro-aggregation factor). In high doses, acetylsalicylic acid also inhibits the biosynthesis of prostacyclin and other antithrombotic prostaglandins (D2 , Eone and etc.). In this regard, acetylsalicylic acid is prescribed as an antiplatelet agent in relatively small doses (75-325 mg per day).
Below is a list of antiplatelet agents:
- Acetylsalicylic acid (Acidum acetylsalicylicum)
- Ginkgo biloba leaf extract (Extractum foliorum Ginkgo bilobae)
- Calcium dobesylate
- Methylethylpyridinol (Methylaethylpiridinolum)
- Xanthinol nicotinate
- Lysine acetylsalicylate (Lysini acetylsalicylas)
- Omega-3 triglycerides [20%] (Omega-3-triglycerides [20%])