In this Chapter:
19.1. Drugs used for the prevention and treatment of thrombosis
19.1.1. Drugs that decrease platelet aggregation (antiaggregants)
19.1.2. Drugs that decrease blood coagulation (anticoagulants)
19.1.3. Fibrinolytic drugs (thrombolytics)
19.2. Drugs that stop bleeding (hemostatics)
19.2.1. Drugs that increase blood coagulation
19.2.2. Antifibrinolitic drugs
The process of hemostasis1 is driven by the thrombogenic system (platelet aggregation and blood coagulation), which is functionally associated with the thrombolytic (fibrinolytic) system. In the organism these two systems are dynamically balanced and the dominance of one or the other system depends on certain conditions. Thus, if the vessel is damaged and bleeding occurs, vessel spasm, platelet aggregation and blood coagulation become activated, thrombogenesis takes place and bleeding stops. Under normal conditions there is no excessive thrombogenesis in the organism because the process of fibrinolysis limits it. Later the fibrinolytic system provides gradual dissolution of the thrombus and restores patency of the vessel. When there is an imbalance between the coagulating and anticoagulating systems, either increased bleeding or extensive thrombosis may occur. Both conditions are corrected by the prescription of the proper medicines.
The drugs that affect thrombogenesis are classified in the following way.
I • The drugs taken for prophylaxis and treatment of thrombosis
= The drugs that decrease platelet aggregation (antiaggregants)
= The drugs that decrease blood coagulation (anticoagulants)
= Fibrinolytic drugs (thrombolytic drugs)
II • Drugs used to stop bleeding (hemostatics)
= Drugs that increase coagulation
□ Drugs that are administered locally
□ Drugs that have a systemic effect
= Antifibrinolytic drugs