To help a patient taking warfarin

pharmachologic effect

Manufacturer: Ozone, Canon Pharma, Russia/Takeda, Denmark
Release form: tablets

Active ingredient: Warfarin

Synonyms: Warfarex, Warfarin Nycomed

Warfarin has an anticoagulant effect due to blocking the synthesis of blood coagulation factors dependent on vitamin K, reducing their content in the blood and slowing down coagulation.

The onset of action usually occurs on the second day of administration, the maximum effect occurs after about a week. After discontinuation of the vitamin-K medication, dependent factors are restored on average within five days.

Warfarin - instructions for use

Doses of Warfarin are calculated experimentally. Depending on laboratory parameters. Before prescribing therapy, the patient is measured with prothrombin time (PTT) - this is the time during which a blood clot forms in response to damage to the vessel; normally it is about 11-16 seconds. Then the international normalized ratio (INR) is calculated - equal to the ratio of the patient's PTV to the PTV of a healthy person. Normally, the INR is 0.85–1.35.

In the first four days of treatment, the patient is given 2 Warfarin tablets per day - once, at the same time. On the fifth day, the INR is determined again, which should increase to 2–3 during treatment, and 2.5–3.5 during heart valve replacement and acute myocardial infarction with complications.

Depending on the indicator, a maintenance dose is prescribed. Usually this is 1-3 tablets per day. INR monitoring is carried out every month, and the dose is adjusted if necessary.

The course of treatment with Warfarin depends on the type of disease and individual characteristics of the body and is determined by the doctor. If necessary, the drug is discontinued immediately.

If a patient is re-prescribed Warfarin, then therapy is started with twice the average dose of this particular patient in the first 2 days, then treatment is continued with the average dose. On the fifth day, the INR is also monitored and, if necessary, the dose is adjusted.

For children, the dose is selected based on body weight, functional state of the liver and INR, the level of which should be the same as in adults. The child is treated under the supervision of an experienced pediatrician. In the instructions for use of Warfarin, doses for children are described in more detail.

How to take Warfarin - before or after meals

It does not matter how you take Warfarin, before or after meals. The main thing is to take it at the same time of day, never missing a dose.

Warfarin dose selection

The most difficult and responsible stage. “Loading” initial doses of warfarin (more than 5 mg) are not recommended.

Dose selection can be carried out both with and without the use of low molecular weight heparins (Fraxiparine, Clexane), both in the hospital and on an outpatient basis. The selection period on average takes from 1 to 2 weeks, but in some cases it increases to 2 months. At this time, you will need frequent INR determinations, up to 2 - 3 times a week or daily. Each time, after receiving the next test result, your doctor will determine a change in the dose of the medication and the date of the next test.

If in several tests in a row the INR remains in the range of 2.0 - 2.5, this means that the dose of warfarin has been adjusted. Further monitoring of treatment will be much easier.

Warfarin analogues that do not require INR control

It is important to decide what to replace Warfarin with so as not to control the INR, since this brings a lot of inconvenience for the patient, frequent visits to the clinic and tests.

Warfarin analogues that do not require INR control include:

• antiplatelet agents - Plavix, Cardiomagnyl, Thrombo ACC, Aspirin Cardio;
• direct-acting anticoagulants - Pradaxa, Eliquis, Xarelto, Clexane.

Prices for Warfarin analogues can be compared in the table

Pradaxa

Manufacturer: Boehringer Ingelheim, Germany
Release form: capsules

Active ingredient: Dabigatran etexilate

Warfarin substitute Pradaxa is a German original drug, a direct-acting anticoagulant, which is converted into an active form in the body and directly and reversibly inhibits thrombin activity. Therefore, this analogue prevents the formation of blood clots.

An analogue of Pradaxa is produced in 75, 110 and 150 mg doses, the therapeutic dose is selected by the doctor. Capsules should not be opened.

The Warfarin analog Pradaxa is used for the treatment of acute thrombosis and thromboembolism and significantly reduces the risk of death from these diseases.

An INR test is not required during treatment with Pradaxa.

Sinkumar

Manufacturer: Meda Pharma, Germany
Release form: tablets

Active ingredient: Acenocoumarol

Analogue Sinkumar is an indirect anticoagulant. Like Warfarin, it is a vitamin K antagonist and inhibits the synthesis of vitamin K-dependent blood clotting factors.

The Warfarin analog Sincumar is used to treat pulmonary thromboembolism, coronary artery thrombosis and phlebothrombosis.

Treatment with Sinkumar should be accompanied by constant monitoring of coagulation parameters, namely prothrombin time and INR.

Clexane

Manufacturer: Sanofi, France
Release form: injection solution

Active ingredient: Enoxaparin sodium

Synonyms: Enixum, Anfibra, Gemapaksan

The Clexane analogue is a direct anticoagulant that acts by inhibiting the function of the thrombokinase enzyme, a blood clotting factor.

Clexane is a low molecular weight heparin, an injection solution with various concentrations of the active substance.

The drug is administered subcutaneously or intravenously; it cannot be used intramuscularly. Treatment is often carried out in a hospital setting for patients on bed rest.

No additional monitoring of blood parameters is required.

What may affect treatment

• Any concomitant diseases (including “colds” or exacerbation of chronic diseases)
• The use of drugs that affect the blood coagulation system. This is especially true for a large class of drugs that includes aspirin. It also includes many drugs prescribed as anti-inflammatory and painkillers (diclofenac, ibuprofen, ketoprofen, etc.). As a mild analgesic during treatment with warfarin, it is better to use paracetamol in normal dosages. In any case, the need for a new medication and the duration of its use must be agreed with the attending physician. When warfarin and aspirin are prescribed simultaneously, the INR is maintained in the range of 2.0 - 2.5.
• The use of drugs that affect the absorption, excretion and metabolism of warfarin. Most often, it is necessary to take into account the prescription of broad-spectrum antibiotics and oral antidiabetic agents. However, taking any new medicine may change how warfarin works. If concomitant treatment is necessary, additional INR analysis is usually prescribed at the beginning and end of therapy.
• Diet changes.

Warfarin acts on blood clotting through vitamin K, which is found in varying amounts in food.

There is no need to avoid foods high in vitamin K! Nutrition should be complete. You just need to make sure that there is no significant change in their proportion in the diet, for example, depending on the season. If you significantly increase your intake of foods rich in vitamin K while on a stable dose of warfarin, this may greatly weaken its effect and lead to thromboembolic complications.

The maximum amount of vitamin K (3000 - 6000 mcg/kg) is found in dark green leafy vegetables and herbs (spinach, parsley, green cabbage), and in green tea up to 7000 mcg/kg; intermediate amounts (1000 - 2000 mcg/kg) - in plants with paler leaves (white cabbage, lettuce, broccoli, Brussels sprouts). A significant amount of the vitamin is found in legumes, mayonnaise (due to vegetable oils), and green tea. Fats and oils contain varying amounts of vitamin K (300 - 1000 mcg/kg), more of it in soybean, rapeseed, and olive oils. The content of vitamin K in dairy, meat, bakery products, mushrooms, vegetables and fruits, black tea, coffee is low (no more than 100 mcg/kg). Regular consumption of berries and cranberry juice may increase the effect of warfarin.

Small doses of alcohol with normal liver function do not affect anticoagulant therapy, but alcohol consumption must be treated with caution.

Taking multivitamins that contain vitamin K may reduce the effect of warfarin.

Warfarin or Aspirin Cardio – which is better?

Manufacturer: Bayer, Germany
Release form: film-coated tablets

Active ingredient: Acetylsalicylic acid

Synonyms: Thrombo ACC, Thrombopol, CardiASK, ASC Cardio

Warfarin analogue Aspirin Cardio is an original German drug that has an antiplatelet effect by blocking the enzyme cyclooxygenase-1, and thus preventing platelet aggregation.

The analogue of Aspirin Cardio is used mainly for prophylactic purposes to prevent cerebrovascular accidents, stroke, acute myocardial infarction, and complications after vascular surgery.

One of the indications for the use of the Aspirin Cardio analogue is stable and unstable angina.

The active ingredient Acetylsalicylic acid in doses of 500 mg has an analgesic, antipyretic and anti-inflammatory effect.

Warfarin or Thrombo ACC – which is better?

Manufacturer: Lannacher, Austria
Release form: film-coated tablets

Active ingredient: Acetylsalicylic acid

Synonyms: Aspirin Cardio, Thrombopol, CardiASK

To thin the blood, Warfarin can be replaced with the Austrian drug Trombo ACC, which contains acetylsalicylic acid in 50 and 100 mg doses. In these tiny doses it has antiplatelet properties.

An analogue of Thrombo ACC can be freely purchased without a doctor’s prescription and taken 1 tablet daily for the prevention of heart attack, stroke, and other diseases accompanied by increased thrombus formation.

An analogue of Thrombo ACC is also prescribed after vascular surgery.

To prevent the negative effects of acid on the stomach, Trombo ACC tablets are coated with a special enteric coating. Therefore, they should not be chewed or divided in half.

Warfarin or Cardiomagnyl - which is better?

Manufacturer: Takeda, Germany
Release form: film-coated tablets

Active ingredient: Acetylsalicylic acid + Magnesium hydroxide

Synonyms: Fasostabil, TromboMag, Trombital

A substitute for Warfarin without INR control, Cardiomagnyl is an over-the-counter complex drug consisting of acetylsalicylic acid and magnesium hydroxide, which is needed to protect the gastric mucosa from the damaging effects of acid. If acetylsalicylic acid is used for a long time without protecting the stomach, it can lead to ulcers or gastritis.

The antiplatelet drug Cardiomagnyl is used for the prevention of cardiovascular diseases characterized by increased thrombus formation, including stroke or heart attack.

For preventive purposes, the Cardiomagnyl analogue is taken 150 mg on the first day, then 75 mg once a day on an ongoing basis.

If there have already been cases of heart attack or stroke, the drug is prescribed 150 mg daily.

Why is this necessary?

If you have suffered deep vein thrombosis of the lower or upper extremities, your doctor will most likely prescribe you indirect anticoagulants.
The main drug in this group today, both here and abroad, is warfarin. In our country, another drug of this group is used quite widely - phenylin. Other coumarin drugs (acenocoumarol, marcumar, marivan) can be used. The recommendations given are mostly applicable to any anticoagulant. The purpose of this medication is to prevent blood clots from recurring, which could cause your condition to worsen or cause life-threatening complications. The risk of recurrence of thrombosis is quite high during the first year after the first episode of the disease, therefore, taking into account various factors, warfarin is prescribed for a period of 2 to 12 months. In rare cases, longer therapy is performed. Indirect anticoagulants have no effect on an already formed blood clot.

To determine the duration of treatment, special (including genetic) blood tests are sometimes required to identify an increased tendency to blood clots.

A very large number of patients around the world receive the treatment you have prescribed. It is used not only in phlebology, but also in such areas of medicine as vascular surgery. In addition to deep vein thrombosis, the basis for prescribing anticoagulant therapy is often previous heart attacks, cardiac arrhythmias, valve and peripheral vessel replacement, and much more.

Warfarin or Xarelto - which is better for thrombosis and atrial fibrillation

Manufacturer: Bayer, Germany
Release form: film-coated tablets

Active ingredient: Rivaroxaban

The imported analogue of Xarelto is an original German drug that has no synonyms. This is a direct-acting anticoagulant, selectively suppresses factor Xa, as a result prevents the formation of blood clots and does not require regular blood tests to determine PTT and INR.

Doses of the Xarelto analog range from 2.5 to 15 mg. The doctor decides which one to use for certain indications.

Doses of up to 10 mg of Xarelto are prescribed for prophylaxis once a day, 20–30 mg per day is required for the treatment of thromboembolism, atrial fibrillation, and venous thrombosis.

Warfarin or Eliquis – which is better?

Manufacturer: Pfizer, USA
Release form: film-coated tablets

Active ingredient: Apixaban

Eliquis is an analogue of Warfarin that does not require INR control; it is a direct anticoagulant.

The drug blocks factor Xa, which stimulates blood clotting, and prevents blood clots.

The American analogue Eliquis is taken to prevent thrombosis during endoprosthetics, stroke and thrombosis in patients with atrial fibrillation.

The Warfarin analog Eliquis is available in the form of tablets of 2.5 and 5 mg. The usual dosage regimen is 2 tablets per day, 2.5 mg for prevention, and 5–10 mg for the treatment of venous thrombosis and pulmonary embolism.

Reviews from patients indicate that the medication is well tolerated.

Monitoring the dose of warfarin

If the dose of the drug is selected, less frequent monitoring is sufficient - first once every 2 weeks, then once a month. The frequency of additional studies is determined separately. The need for an extraordinary determination of the INR may arise in a number of cases, which we will discuss below. If in any doubt, ask your doctor for advice.

Currently, there are portable devices for self-determination of INR (similar to systems for monitoring blood sugar levels in patients with diabetes), but their cost is very high and, in most cases of deep vein thrombosis, purchasing them is impractical.

Warfarin or Phenilin

, Ukraine
Release form: tablets

Active ingredient: Phenindione

Warfarin analog Phenilin is an indirect anticoagulant that blocks the enzyme K-vitamin reductase. It is used for the treatment and prevention of thrombosis and embolism, for prosthetic heart valves.

Doses are selected based on laboratory tests.

The disadvantage of the Phenilin analogue is the requirement for constant monitoring of not only prothrombin time and INR, but also regular analysis of coagulograms, thromboelastograms and platelet counts.

Warfarin and pregnancy

During pregnancy, taking warfarin is contraindicated. In the event of pregnancy, indirect anticoagulants are immediately discontinued; if further prevention of thrombosis is necessary, heparins are usually used. Therefore, if you suspect pregnancy, refrain from taking the drug until you consult your doctor.

It is possible to use warfarin during breastfeeding. Warfarin is excreted in breast milk in extremely small quantities and does not affect the baby's blood clotting processes, but for complete safety it is recommended to refrain from breastfeeding during the first three days of the mother's treatment with the drug.

Answers on questions

How to replace Warfarin for atrial fibrillation

With atrial fibrillation or atrial fibrillation, the risk of blood clots increases; to prevent this phenomenon, Warfarin analogues and substitutes are prescribed - direct or indirect anticoagulants.

When is it better to take Warfarin - morning or evening?

The time of day does not matter when taking Warfarin. It is important to take regularly, at the same time.

Warfarin - direct or indirect anticoagulant

The drug belongs to the group of indirect anticoagulants, since it does not act directly on thrombin, but as a vitamin K antagonist.

It is important

Always tell any health care professional you see that you are taking anticoagulants. It is advisable to carry your “account” book or treatment diary with you.

Most dental procedures (except tooth extraction) can be performed without changing your treatment regimen. When removing a tooth, it is usually sufficient to use a tampon with a local hemostatic agent (aminocaproic acid, thrombin sponge).

If you have problems with blood pressure, you need to regularly monitor it and maintain it at a level not higher than 130/80 mmHg.