Warfarin is an antithrombotic agent that reduces blood clotting.
Antikoagulyativnoe (prevents the formation of blood clots) warfarin due to its ability to reduce the activity of vitamin K, which provides a synthesis in the liver of blood clotting factors. Warfarin is an anticoagulant indirect action, that is, does not directly affect blood clotting factors.
Because the drug does not affect the already formed coagulation factors, the effect of Warfarin develops slowly. Indirect anticoagulants are prescribed for long-term need to reduce blood clotting, as well as venous thrombosis to prevent the formation of blood clots repeated. Warfarin can reduce the risk of blood clots (thrombi). Optimal effect of the drug can be observed in 3-5 hours from the start of application, as it is lost during the same time after the last dose of warfarin.
This drug is absorbed into the digestive tract almost completely. The binding of warfarin to plasma proteins - 97-99% is excreted in the urine.
Indications for use of warfarin
Warfarin, user confirms, is effective in the following cases:
- therapy and prevention of the formation of clots and blockages in the blood vessels;
- severe thrombosis in the veins;
- blockage of the pulmonary artery;
- the formation of blood clots in the blood vessels after surgery;
- recurrent myocardial infarction;
- recurrent venous thrombosis;
- prosthetic heart valves and blood vessels;
- as an integrated part in the drug or surgical treatment of thrombosis;
- Education recurrent blockages of the pulmonary artery;
- blood clots in the arteries of the brain, heart and peripheral vessels;
- the prevention of occurrence of blockages in the blood vessels, and thrombosis after myocardial infarction.
Instructions for use of warfarin
Warfarin, the use of which should be carried out under the supervision of a physician, is produced in the form of tablets containing 2, 5 mg, 3 mg or 5 mg of active substance.
Tablets are taken 1-2 times a day with water. The most optimal dosage of warfarin and treatment duration determined by the attending physician.
Dose is determined in accordance with parameters such as blood clotting, clinical situation, the body's response to treatment, and generally from 2 to 10 mg per day. As a rule, the rate of warfarin is 6-12 months. During the operation at high risk of thromboembolic complications of warfarin starts 2-3 days before surgery
Warfarin, whose side effects are described in the instructions can cause undesirable effects such as:
- bleeding, anemia, bruising, necrosis due to local thrombosis;
- hair loss, dermatitis, rashes;
- abdominal pain, diarrhea, vomiting, nausea, jaundice, cholestasis, hepatitis, increased liver enzymes;
- cold sensation, paresthesia (numbness), vasculitis (inflammation of blood vessel walls) staining toes in purple;
- headache, fatigue, dizziness, taste disturbance, asthenia;
- fever, rash, swelling, skin rash and itching.
Side effects of warfarin may also manifest as swelling, bruising, skin patches on various parts of the body.
Contraindications to the use of warfarin
If the patient was appointed Warfarin, instruction necessarily should be studied, since in some cases the use of this drug is prohibited:
- disease with a high risk of bleeding;
- state, accompanied by blood dyscrasias;
- recently undergone surgical intervention with a wide surgical field, cranial or ophthalmic surgery;
- diseases of the respiratory system, urogenital system, digestive tract ulcerative lesions with a tendency to bleeding;
- aneurysms (bulging of the wall of the artery or vein);
- cerebrovascular hemorrhage (pathological changes of cerebral vessels);
- pericarditis (inflammation of the serous membrane of the heart);
- bacterial endocarditis (inflammation of the lining of the heart);
- acute disseminated intravascular coagulation (blood clotting due to release tromboplasticheskih substances);
- severe hypertension;
- severe liver or kidney disease;
- pregnancy, threatened abortion;
- inadequate monitoring of patients, psychosis, disorganized patient, alcoholism;
- diagnostic procedures with the threat of uncontrolled bleeding nature (spinal tap);
- malignant hypertension;
- extensive regional anesthesia.
Because breast milk drug is released in inactive form, warfarin breastfeeding women should take place under medical supervision.
According to the instructions, warfarin should be stored at room temperature in a dry place. Shelf life of warfarin is 5 years.