Anticoagulants: a list of drugs of direct and indirect action

Vascular diseases often lead to increased blood clotting and thrombosis.

Such a pathological process is extremely dangerous for health, because it can trigger the development of a heart attack or stroke. In this situation, the only correct way out will be the appointment of anticoagulants - drugs that promote blood thinning.

Increased blood clotting - a deviation observed in varicose veins, thrombophlebitis, hemorrhoidal thrombosis of veins, strokes, heart attacks, arterial injury in atherosclerotic disease, thromboembolism. Thrombosis can also occur due to shock. You can avoid such adverse effects by taking anticoagulants.

What it is?

Anticoagulants are called medical drugs that reduce blood clotting rates. Thus, they prevent the formation of blood clots. This effect is achieved by reducing the formation of fibrin.

The components of blood thinning drugs have an effect on blood viscosity, inhibiting the process of blood clotting. They are used both for therapeutic and prophylactic purposes. It can be tablets, ointments, gels, creams, injections. A specific drug, as well as the form of its release, can be appointed exclusively by a specialist - therapist, cardiologist, phlebologist or family doctor.

Self-treatment in this case can lead to very serious consequences.


Anticoagulants, according to the generally accepted classification, are:

  1. Physiological. Such substances are regularly produced by the cells of the body and are independently released into the bloodstream. Physiological anticoagulants, in turn, are primary (those that are constantly synthesized) and secondary (are produced after the splitting of blood flow factors after the dissolution of fibrin in it).
  2. Pathological. By identifying them in the blood plasma, one can judge the development of a disease.

What is prescribed?

Anticoagulants are extremely necessary for patients with:

  • stroke caused by thrombosis or embolism;
  • atherosclerotic blood vessel disease;
  • rheumatic heart disease;
  • thrombophlebitis;
  • impaired functioning of a three-fold snort (congenital or acquired);
  • thrombosis stage 2;
  • varicose veins;
  • aortic aneurysm;
  • ischemic heart disease;
  • pulmonary embolism;
  • syndrome desimenirovannogo intravascular coagulation;
  • thromboangiitis;
  • obliterating endarteritis;
  • atrial fibrillation.

Self-treatment with anticoagulants is strictly prohibited, as the wrong dosing regimen can lead to serious consequences, including hemorrhagic stroke. With caution, these drugs are prescribed to patients suffering from frequent bleeding due to poor blood clotting. In such cases, the doctor selects anticoagulants that have a sparing effect on the body.

Direct and indirect anticoagulants - what's the difference?

Depending on the mechanism of action of anticoagulants are:

  1. Straight. This group of antiplatelet agents act directly on thrombin, reducing its activity. This is a kind of inhibitors of thrombin, which neutralize its effects, thereby preventing the process of blood clots. When treating with direct anticoagulants, it is necessary to monitor the ESR indicators in order to avoid bleeding. Absorption of such drugs occurs in the digestive tract. They are derived mainly by the kidneys.
  2. Indirect. Such drugs affect the biosynthesis of side enzymes of the system responsible for blood clotting. Indirect anticoagulants completely destroy thrombin, and do not block its activity. In addition to blood thinning, such antiplatelet agents help relax smooth muscles, remove urates from the body, and also improve the blood supply to the myocardium. Indirect anticoagulants are suitable for the treatment and prevention of thrombosis.

In a separate group, you can make drugs that lower blood clotting, but act on a different mechanism. These include Aspirin, Acetylsalicylic acid, etc.

Direct acting anticoagulants

The main objectives of this group of anticoagulants are:

  • prothrombin deactivation;
  • thrombin inhibition;
  • inhibition of the thrombosis process.

In order to avoid the opening of internal bleeding throughout the entire period of therapy, it is necessary to monitor the ESR indicators. Direct anticoagulants are divided into:

  • heparin;
  • low molecular weight heparin;
  • lepirudin;
  • hirudin;
  • sodium hydrocitrate;
  • danaparoid

Below are brief reviews of each of the above groups of direct anticoagulants.


Perhaps the most common and well-known anticoagulant. It is applied in several ways:

  • by intravenous administration;
  • intramuscularly;
  • subcutaneously.

For external application (for varicose veins or thrombophlebitis) it is used in the form of a special Heparin ointment. Patients respond well to use:

  • Adreparin;
  • Parnaparin;
  • Nadroparin sodium;
  • Dalteparina;
  • Tinzaparin;
  • Enoxaparin;
  • Reviparina.

Often, anticoagulants for topical use are not very effective. It is advisable to use them for varicose veins of the lower extremities, hemorrhoids, bruises.

If we talk about more potent anticoagulants, then you can add to this list:

  • Heparin ointment;
  • Lioton;
  • Venolife;
  • Trombless;
  • Troxevasin Neo;
  • Hepatrombin.

Heparins can also be used for subcutaneous and intravenous administration. Such drugs are selected individually and cannot be replaced by analogs in the event of hypersensitivity reactions in patients or other manifestations of side effects.

Injectable heparins begin to act 3 hours after administration, and their effect lasts for a day. Under the influence of these drugs, the production of thrombin is reduced, and other processes that affect blood clots are blocked.

Treatment of cardiovascular pathologies - angina, heart attack, PE or deep vein thrombosis of the lower extremities - use Deltaparin, Enoxaparin, Nadroparin.

For prophylactic purposes, Heparin or Reviparin is used to prevent thromboembolism and thrombosis.

Indirect anticoagulants

Indirect anticoagulants are called medications that have the opposite effect to that of vitamin K. The following drugs are the most effective.


Anticoagulant drug of indirect action, which has the ability to penetrate the histohematogenous barrier. A distinctive feature of the drug is its ability to accumulate in the tissues of the body.

According to the patient reviews, this medicine is one of the most effective. Its use contributes to the normalization of the blood and puts in order indicators of ESR. After completing the full course of therapy, all unpleasant symptoms completely disappear. However, Fenilin can cause a number of side effects, so in recent years it has been less and less applied in practice.


Neodicoumarin is a drug whose main action is to prevent the formation of blood clots. However, the therapeutic effect of drugs is noted not immediately, but only after some time.

Neodicoumarin also contributes to:

  • suppressing the activity of the coagulant system;
  • lipid reduction;
  • increased vascular permeability.

During the entire course of therapy, it is necessary to strictly observe the dosage regimen of the medicine developed by the doctor.


Warfarin is the most commonly prescribed drug belonging to the group of indirect anticoagulants. Under the influence of its components, the process of the production of blood clotting factors by the liver is suppressed. It is due to this that thrombosis is prevented.

Warfarin is a fast-acting drug with a lasting effect. But it can cause serious side effects that disappear after reducing the dosage or completely canceling it.

Warfarin increases the risk of stroke and bleeding during self-medication. Therefore, the medication should be administered exclusively by a doctor!

Antiplatelet agents

Antiplatelet agents - drugs that reduce blood clotting by preventing the process of gluing platelets. As a rule, they are prescribed in parallel with anticoagulants to enhance the therapeutic effect.

Under the influence of antiplatelet agents, the lumen of the blood vessels expands, pain is eliminated and inflammation is relieved. The most famous anticoagulants of this group are described below.


Aspirin is dispensed in the form of tablets for oral administration, so it is suitable for home treatment. The drug has a vasodilator effect, prevents adhesion of platelets and thrombosis.


The drug reduces the intensity of gluing platelets, increases the duration of bleeding and improves capillary blood circulation. It is assigned to patients with coronary artery disease, myocardial infarction, cerebrovascular disorders. The main objective of treatment is to prevent thrombosis.


Tirofiban is a drug used in complex treatment. Often, he is appointed in parallel with Heparin, which helps to increase the antithrombotic effect of both drugs.


Under the influence of the medication, the lumen of the coronary vessels expands, blood thinning, and improvement of the heart muscle supply. In parallel, the blood supply to the brain is normalized and blood pressure decreases.

What is the INR?

INR is the ratio of 2 blood counts:

  • before starting warfarin treatment;
  • while taking warfarin.

The abbreviation stands for "International Normalized Relationship." INR is an important indicator based on an assessment of the ratio of the generally accepted prothrombin time to the patient PTV. Normally, the INR values ​​range from 0.85 to 1.25. During the course of treatment with warfarin, an INR level of 2 to 3 units should be reached.

INR is determined before starting treatment. Repeated analysis is carried out after 2 to 5 days. After selection of the dosage of the medicine necessary for a specific patient, monitoring of the INR indicators is carried out once every 14 to 28 days.

  1. When INR is less than 2, the dose of warfarin is increased by 1 tablet per week to obtain a therapeutic response. Indicators INR are determined weekly.
  2. With INR more than 3, the dosage is reduced by 1 tablet per week. Monitoring of the INR is carried out a week after lowering the dose.
  3. When INR is 3.51 - 4.5, the dose of warfarin is reduced by 1 tablet. The control study is performed after 3 days.
  4. With INR 4.51 - 6, the dosage of the drug is reduced by 1 tablet. Monitoring indicators carried out through the day.

If the INR exceeds 6 units, warfarin is completely canceled.

The main contraindications to receive

Anticoagulants are strictly prohibited to take when:

  • gastric ulcer or duodenal ulcer;
  • hemorrhoids, accompanied by the release of blood;
  • hepatitis;
  • chronic fibrotic changes in the liver tissues;
  • hepatic and renal failure;
  • urolithiasis;
  • thrombocytopenic purpura;
  • pericarditis;
  • endocarditis;
  • vitamin C and K deficiency;
  • cavernous pulmonary tuberculosis;
  • cancer of any location;
  • hemorrhagic pancreatitis;
  • brain aneurysm;
  • leukemia;
  • myocardial infarction, accompanied by arterial hypertension;
  • chronic alcoholism;
  • Crohn's disease;
  • hemorrhagic retinopathy.

Anticoagulants are contraindicated during pregnancy and lactation. They are also not recommended to be taken during menstruation, as well as in the early postpartum period, as they can cause increased bleeding. Such drugs are contraindicated in elderly patients.


Anticoagulants are drugs that are important for maintaining the normal functioning of the cardiovascular system and preventing the development of damage to the health and life of the heart and blood vessels. Self-medication by this group of medications is unacceptable, since they have many contraindications, and can provoke the occurrence of serious side effects. Uncontrolled use of anticoagulants can lead to bleeding, including internal, hidden.

In view of such consequences, it is important that blood thinning medications be prescribed exclusively by a doctor, since a responsible approach to dose titration is required here. In addition, throughout the entire period of therapy should be carefully monitored indicators of blood.

Antigulants should not be confused with antiplatelet agents and thrombolytics. The mechanism of action of the first two groups of drugs is aimed at preventing or slowing the development of a blood clot. But thrombolytics are administered intravenously, and under their influence the blood clot is completely destroyed.

Watch the video: Pharmacology - ANTICOAGULANTS & ANTIPLATELET DRUGS MADE EASY (April 2020).


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