The process of blood coagulation proceeds in several phases. The first is thromboplastin formation, the second is thrombin formation, and the third is fibrinogenesis. For normal flow of each phase in the blood should be an anticoagulant. If natural physiological substances are not enough, then they are imitated - drugs are injected.
Indications for the use of antiplatelet agents
Antiagreganty - drugs that have a depressing effect on the process of blood clotting. According to the anticoincidence mechanism, they are divided into 2 groups:
- direct action (heparinoids, heparin);
- indirect action (derivatives of phenylidandione and oxicumarin).
Today, there are also antiplatelet agents of a new generation - disaggregants. They have an inhibitory effect on the aggregation capacity of platelets.
Appointment of all groups of drugs can be either individually or together. The main indications for the use of anticoagulants are signs of hypercoagulable blood (prethrombotic state) and thrombotic process of different localization. The patient is recommended to take these medications even with a thrombotic process in the coronary artery system, as this is one of the effective methods for preventing large-focal and transmural myocardial infarction .
Contraindications to the use of antiplatelet agents
Modern antiplatelet agents can not be prescribed if the patient has a disease:
- digestive apparatus (even in cases with a tendency to bleeding);
- kidney with symptoms of hematuria;
- liver with severe impairment of its function.
It is not recommended to take this group's medicines if there are symptoms of kidney failure, violations of haemostatic mechanisms, C- and K-vitamin deficiency and acute heart aneurysm.
These drugs can cause side effects. They are especially evident when using anticoagulants of direct or indirect action. Disaggregants have practically no negative effect on the body.
The most common side effects of antiplatelet agents are:
- allergic reactions;
- headache;
- hemorrhagic complications;
- bleeding of another localization.
List of antiplatelet agents
Anticoagulants of direct effect directly affect the factors of blood coagulation in the vascular channel. The therapeutic effect with intravenous injection occurs almost immediately and lasts 6 hours. The list of antiplatelet agents of this group includes:
- Heparinolds;
- Heparin;
- Arvin;
- Calcium heparinate;
- Chondroitin sulfates A and C.
The most commonly used is Heparin. It quickly inhibits the formation of fibrin and prevents the agglutination of the blood platelets.
The list of antiaggregants of indirect action includes:
- Dicoumarin;
- Cincumar;
- Nafarin;
- Neodikumarin;
- Phenylin;
- Omefin.
They inhibit blood clotting only in the body. The effect after application comes in 24-72 hours and lasts up to several days. It is thanks to this property that the drugs of this group are more convenient for long-term treatment.
Disaggregants in the classification of antiplatelet agents occupy a special place. All by the fact that they have little effect on the coagulation activity of the blood. But at the same time they block or inhibit the adhesion-aggregation properties of the plates. Therefore, in combination with other drugs and antiplatelet agents, they
- Butadione;
- Papaverine ;
- Anturan;
- Indomethacin;
- Imizine;
- Carbocromene;
- Parmedin.
All these disaggregants with some caution should be prescribed to persons of elderly and senile age.