Memo for a patient taking Warfarin (CHD Health School)

Even if the doctor explained in detail what dosage to take Warfarin, the instructions for use should still be thoroughly studied by the patient. This drug has an indirect effect directly on blood clotting, that is, it acts as an indirect anticoagulant. The peak effect occurs 3-5 days from the start of use. The action of the tablets, at the correct dosage, is aimed at the synthesis of side enzymes that regulate blood clotting, but thrombin is not affected at all.

Historical reference

In the early 20s, an outbreak of a hitherto unknown bovine disease was registered in the United States, and later Canada. Cows often began to spontaneously bleed; for example, after dehorning, 24 out of 25 animals died. The gap also affected males - only 14 out of 30 bulls survived the castration procedure. The reason for the increased mortality was simple blood loss.

The secret of the disease was discovered by butcher-pathologist Frank Schofield in 1921. He found out that the dead animals ate moldy silage from sweet clover, which is a powerful coagulant. To confirm his theory, he conducted an experiment with rabbits, giving one group of individuals spoiled hay and the other fresh hay. The moldy stems of the plant caused multiple bleeding in animals and led to death. After 8 years, veterinarian Roderick L.M., based on experiments, revealed that their condition was directly related to the insufficient functioning of prothrombin.

Warfarin is prescribed to patients for life while monitoring blood clotting

Unfortunately, the anticoagulant substance from sweet clover could not be isolated until 1940. After synthesis, it received the name dicumarol. It was obtained from plant coumarin molecules. It is its sweetish smell that we feel when inhaling the aroma of freshly cut grass. Dicumarol became the first anticoagulant patented in 1941. The drug Warfarin was synthesized after 7 years. And the history of its origin is no less interesting.

Warfarin was first officially registered and used as an effective poison to kill rodents. But doctors began to think about a more useful use of the drug after an incident with a US military conscript who tried to commit suicide with the help of this substance. He was taken to intensive care and treated with an increased dose of vitamin K, resulting in a full recovery. Doctors noticed that the use of Warfarin in the doses indicated in the instructions inhibits an enzyme called epoxide reductase, disrupting general metabolism and having a powerful effect on blood viscosity.

After this, studies began on the use of a drug containing Warfarin as a therapeutic anticoagulant. It is noteworthy that one of the first patients to receive these pills was President Dwight Eisenhower, who survived a heart attack. There is a theory that it was with Warfarin that his closest associates tried to poison even Joseph Stalin himself; the substance has no color or taste and, according to the symptoms of its effects, completely coincides with the clinical picture that appeared in the dictator.

When is medical attention required?

Medical attention is needed if:

• a pregnant woman, an elderly person, a child were injured;
• there are clear signs of external or internal bleeding;
• suddenly my health suddenly deteriorated.

Depending on the severity of the condition, assistance is provided on the spot or hospitalization is carried out in a specialized department of the hospital, where treatment continues:

• stop taking the drug until the target INR level is reached, if necessary, replace Warfarin with low molecular weight heparin;
• transfusion of prothrombin complex factor concentrates, fresh frozen plasma or whole blood;
• administration of vitamin K in a dose of 5–10 mg by slow intravenous infusion, if necessary, repeated administration after 12 hours;
• treatment of developed complications.

Pharmacokinetics of the drug

After use, Warfarin is absorbed into the stomach almost completely. It binds to liver proteins by 97-99%. According to the instructions, the substance is also metabolized in liver cells.

Warfarin Nycomed is a racemic mixture, but the R- and S-isomers are metabolized separately. They form 2 different metabolites.

The catalyst for the S-enantiomer is the enzyme CYP2C9, respectively, for the R-enantiomer it is CYP1A2 and CYP3A4. The levorotatory isomer has approximately 2-5 times increased anticoagulant activity (according to the attached instructions). If a patient experiences a polymorphism of the CYP2C9 enzyme after using the substance, then he may have too much sensitivity to the active substance Warfarin, which increases the risk of internal bleeding.

According to the instructions, after use, Warfarin is safely excreted from the human body along with urine (with bile). The process takes from 20 to 60 hours after the end of the reception. In this case, the R-enantiomer may require up to 90 hours, and the S-enantiomer only 44 hours.

Contraindications to the use of Warfarin

These drugs are contraindicated for any diseases and pathological conditions that carry a risk of bleeding, the danger of which increases if an overdose of Warfarin occurs:

• Hematuria of any origin
• Peptic ulcer of the stomach and duodenum
• Ulcerative colitis
• Urolithiasis disease
• Urolithiasis
• Pregnancy (in addition to the high risk of uterine bleeding, you should be wary of the teratogenic effect that Warfarin has)

This drug should be used with caution in patients with liver pathology. Firstly, it itself reduces its function and can cause liver damage. Secondly, against the background of liver pathology, there may be an undiagnosed vitamin K deficiency, which makes it difficult to select the dose of the drug and increases the risk of overdose.

Admission rules

Warfarin is often prescribed to patients for life. But in order for the treatment to bring only benefits, you should adhere to a number of simple rules described in the instructions:

• regularly take blood tests to monitor blood clotting indicators;
• take Warfarin of the same brand;
• adhere to the diet prescribed by the doctor, which usually includes a large number of foods containing vitamin K (cabbage with dark green leaves, salad);
• exclude cranberry juice from the diet (it is also contraindicated in the instructions);
• Closely monitor bleeding (for example, while brushing your teeth or during menstruation) and bruising and report them to your doctor;
• Under no circumstances should you change the dosage of Warfarin yourself;
• consult a doctor and follow the instructions before starting parallel intake of vitamins, dietary supplements or herbal infusions (teas, decoctions);
• limit the consumption of alcoholic beverages;
• at an appointment with a doctor (dentist, etc.), inform him that you are a patient taking Warfarin;
• If you experience any side effects related to your health, contact your doctor immediately.

Signs of overdose

The main sign of an overdose of Warfarin is increased bleeding, manifested in the occurrence of bleeding, both obvious and hidden. Patients taking the drug should pay attention to the appearance of certain signs that may directly or indirectly indicate a complication that has developed.

Indirect signs of warfarin overdose:

• bleeding gums when brushing teeth or eating solid foods;
• spontaneous nosebleeds;
• the appearance of small hematomas not associated with previous trauma;
• prolonged bleeding from wounds, even minor ones, that does not correspond to the degree of damage;
• in women, menstrual flow is heavier and longer than usual.

Clear signs of overdose (require immediate medical attention):

• black, tarry stools (melena) or coffee-ground vomit;
• coloration of urine - from pink to intense red;
• excessive bleeding from the nose or gums;
• in women – prolonged heavy menstruation, intermenstrual bleeding;
• cough with streaks of blood in the sputum;
• a sharp decrease in blood pressure, tachycardia, palpitations, shortness of breath;
• bleeding from minor wounds and cuts lasting more than 10 minutes;
• dizziness, severe headache, difficulty speaking, noise, ringing in the ears;
• visual impairment (double vision, flickering “spots” before the eyes, decreased visual acuity);
• sudden coldness of the extremities, numbness, feeling of goosebumps crawling on the skin, limitation of movements in the extremities;
• loss of coordination, unsteadiness of gait;
• sudden intense pain in the abdominal or chest cavity;
• extensive hematomas, areas of swelling that appear without connection with traumatic effects;
• massive swelling of the lower extremities.

Manufacturers and possible dosage of tablets

Warfarin, the tablet of which may differ in dosage, is produced by several European and domestic factories. The most common drugs in the pharmacy chain are from Orion Corporation (manufactured in Finland), Pharma Start (Ukraine, the most budget option), Takeda Pharma (Denmark or Poland). Instructions for the medication are always included.

The medicine Warfarin is available in the following forms:

• FS tablets of 2.5 and 3 mg (packaged in bags, containers);
• tablets No. 10 and No. 100 (this is how the number of units in the blister is indicated);
• Warfarin Sodium Clathrate is a white or colorless powder in double packaging, intended and directly used for the production of solutions and non-sterile dosage forms;
• Warfarin Nycomed - most often packaged in 100 tablets with a dosage of 2.5 mg;
• Orion - tablets containing 3 and 5 mg of the active substance (30 pieces per package), in liquid form have a volume of 100 mg (bottle).

This drug is not available in the form of suppositories or ampoules. The use of the active substance in this way is not intended.

What is the drug

Warfarin is highly effective.
Regular use of the drug significantly reduces the risk of blood clots, which, in turn, can provoke the development of a stroke, lead to venous thromboembolism and heart attack, and also cause other pathologies that can be fatal. The main rule that people who regularly use Warfarin should adhere to is to follow the dosage of the drug so as not to provoke bleeding.

Warfarin instructions contain an indication of the dose, but only the attending physician can determine how to take the medicine. Self-medication can lead to the most negative consequences.

Warfarin is an indirect anticoagulant

Warfarin is a medicine available in tablet form. It belongs to a number of anticoagulants - drugs that reduce blood clotting. This is necessary when the body is prone to blood clots and the development of cardiovascular pathologies.

A component of the tablets blocks partial production of vitamin K, which in the body is responsible for blood thickness. That is, the less of this vitamin, the less blood clots.

With increased blood density, the risk of blood clots increases, which significantly impairs vascular patency and in some cases can lead to death.

Warfarin is available in tablet form, and each of them contains the following components:

• main substance – warfarin sodium salt
• additional components – anhydrous lactose, magnesium stearate, corn starch

The drug is available in different dosages of warfarin - 1 mg, 2 mg and 5 mg.

Warfarin analogs

For patients who have previously successfully used Warfarin in their treatment and prevention of blood clots and have not observed changes in INR levels, there is no point in switching to another drug. This may only be required directly if the instructions identify direct contraindications and the risk of bleeding is too great. For replacement, the doctor may prescribe the following medications:

• Dabigatran (Ethexilate);
• Heparin injections are very effective; low molecular weight options are also used, for example, Enoxaparin (Clexane);
• Aspirin (Astrid, Cartia);
• Rivaroxaban (Xarelto, according to the instructions, they are completely identical in action);
• Dipyridamole (imported names - Asasantin Wed, Persantin Wed);
• Apixaban (Eliquis will need to adjust the dosage, it may differ from the original instructions);
• Clopidogrel (you can find Plavix, Iskover in the pharmacy).

Interestingly, these medications rarely require INR and PRI monitoring. However, according to the instructions, they have a number of dangerous side effects, which are recommended to be discussed with your doctor before using the medicine.

Composition, properties and release form of the drug

Warfarin is made in the form of tablets that are round in shape and light blue in color, with a cross mark on them.

The tablets are sold in plastic jars containing 50 or 100 pieces. You can buy the medicine at a pharmacy without a doctor's prescription.

As for the composition, its main active ingredient is warfarin sodium. The amount of the active component may vary (from 1 to 5 mg), depending on the release form.

Pharmacotherapeutic action and indications for use

Warfarin Nycomed, according to the instructions, has an anticoagulant effect. It is aimed at significantly slowing down or completely inhibiting the synthesis of factors that are associated with blood coagulation in the liver, which occurs under the influence of vitamin K. But it should be understood that according to the instructions, the drug is an indirect anticoagulant, so during use it does not cause clotting directly in the blood channel, but begins to act only a couple of days after administration.

Warfarin's instructions for use are quite extensive. The drug must be prescribed to people at risk of developing embolism or blood clots. Under the supervision of a doctor and in accordance with the instructions, the medicine can be prescribed for the following diagnoses:

• varicose veins – varicose veins in the legs or torso;
• thrombophlebitis – veins are contaminated with harmful cholesterol;
• acute or chronic venous thrombosis (take according to individual dosage);
• secondary myocardial infarction (Warfarin is prescribed for life);
• a blood clot formed in the lungs (pulmonary embolism);
• thrombosis of cerebral or peripheral or coronary arteries;
• haemorrhoids;
• thromboembolism;
• transient ischemic attacks that develop into strokes - especially if there is a risk of death.

Warfarin Nycomed is often taken in the postoperative period, when the body is full of medications designed to stop bleeding. When replacing heart valves and blood vessels, the medication is often combined with acetylsalicylic acid, according to the instructions.

Warfarin is prescribed in the postoperative period to prevent bleeding

Composition of Warfarin tablets

The 4-hydroxycoumarin contained in the drug is an indirect anticoagulant. This means that the slowing down of blood clotting occurs not under the influence of the medication itself, but due to its pharmacological effects in the body, that is, in an indirect manner.

Blood thinning occurs due to blocking the formation of coagulation factors - II (prothrombin), VII, IX and X. They are called vitamin K dependent, since they can only be synthesized in its presence.

When Warfarin enters the body, the rate of production of these compounds by the liver drops by almost half, and their activity decreases to 30%. But since there are already ready-made and complete factors in the blood at the time of treatment, it takes time for the effect to occur. It is individual for each person, most often it is 3-7 days of admission.

In order to restore previous indicators or increase coagulation, approximately the same time period is needed after the end of use.

Contraindications and dangers of the drug

The instructions included with Warfarin also describe a number of contraindications to the use of the drug. For example, it should not be used by patients prone to bleeding and suffering from anemia. Warfarin is contraindicated in the following cases:

• bacterial endocarditis;
• pregnancy (Warfarin is strictly prohibited in the 1st trimester and in the last 4 weeks of pregnancy);
• lactation period at any age of the child (breastfeeding);
• acute syndrome (stages 2 and 3) of disseminated intravascular coagulation;
• clearly visible aneurysm;
• lumbar puncture (prohibited in any cases);
• period of menstruation;
• deficiency of category C and S proteins (strictly prohibited in the instructions);
• cerebrovascular hemorrhages;
• peptic ulcer of the walls of the stomach, any part of the gastrointestinal tract or damage to the duodenal mucosa;
• malignant (or turning into a cancerous tumor) arterial hypertension;
• thrombocytopenia (prohibited in the instructions);
• severe arterial hypertension;
• exudative and no less dangerous bacterial pericarditis;
• liver or kidney failure;
• hemorrhagic stroke, intracranial hemorrhage caused by injury or disease;
• varicose veins affecting the veins located in the esophagus.

You should not take the drug to patients who cannot take blood tests exactly on schedule to monitor the level of blood clotting. According to the instructions, Warfarin is prohibited for people who are unable to independently control the dosage and strictly follow the doctor’s recommendations.

The use of the drug is not prescribed for recent ophthalmological (performed on the eyes) and craniocerebral operations, as well as for extensive surgery in the torso area (chest, back, abdominal area). The medicine is also dangerous for patients with hypersensitivity to Warfarin.

Use of the drug, including long-term use

Patients must take the drug at a strictly defined time of day. To do this, you need to determine in advance the best option for yourself and stick to it throughout the entire course of treatment.

In healthy people, it was taken as one for the convenience of monitoring anticoagulant therapy. The doctor’s recommendation may be to bring the INR to 2 or 3, that is, the fluidity of the blood will increase two or three times compared to the original. The frequency of checking the INR is once every 1 - 2 months.

How to take Warfarin?

When starting to take Warfarin Nycomed, you must read the instructions for use. But it is equally important to get a personal diary with a table. It is convenient to note changes in the dosage of the drug and maintain an exact schedule for its daily intake. Warfarin is taken at the same time every day!

Your doctor will tell you in detail how to take the medicine. The tablet can be taken both before and after meals. It must be swallowed whole with a sufficient amount of liquid. Do not chew or crush the pill in any other way.

How and in what quantity is warfarin prescribed?

The instructions for use of warfarin explain in detail how and in what quantities it is permissible to take the drug. Most often it is prescribed in tablets, once a day every day, preferably at the same time (usually 17:00), so that the intervals between tablets are approximately the same. The duration of therapy is determined by the attending physician.

Before starting treatment, possible contraindications are carefully assessed, and the INR (international normalized ratio), which characterizes the state of hemostasis, is determined. When taking warfarin for a long time, the INR must be constantly monitored by testing at least once a month. If necessary, the drug can be discontinued immediately, without a period of dosage reduction.

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If the patient has never used warfarin before, then the initial dose is 5 mg per day for the first four days of treatment. On day 5, the patient donates blood for an INR test, depending on the values ​​of which the maintenance dosage is determined, usually up to three tablets (up to 7.5 mg per kg of weight).

In cases where there is already experience in using an anticoagulant, the doctor prescribes a starting dose for the first two days of use, which is double that taken previously. From the third day, therapy is carried out with the maintenance dose that the patient has already taken. On day 5, the INR is determined and, if necessary, the amount of medication is adjusted.

Children are a special category of patients whose use of warfarin is limited and is carried out under the strict supervision of a physician. The starting dose is 0.2 mg per kg daily if the liver is functioning normally, otherwise it is halved to 0.1 mg/kg. The maintenance dosage is set depending on blood clotting parameters. The target INR level for treatment is the same as for adult patients.

At each stage of the child taking warfarin, clotting is monitored and the dose of the medication is adjusted. As the INR increases, it decreases until it is completely canceled when it exceeds 3.5, and then the intake continues in a reduced amount.

Elderly patients often take warfarin tablets for a long time and even for life; there are no specific recommendations (except for a possible dose reduction) for therapy in this category of patients, however, constant monitoring is the key to safe treatment, since the risk of adverse reactions increases with age.

Disorders of the liver can change the effect of the drug, since the organ synthesizes coagulation factors, but with pathology there are fewer of them, and sensitivity to warfarin is higher. The dose is selected according to the INR and is often lower than that prescribed in accordance with age and pathology.

Kidney disease, on the contrary, does not in any way affect the anticoagulant treatment regimen; the dosages are as recommended by the instructions and the doctor. Peritoneal dialysis for chronic renal failure also does not require treatment adjustment.

The drug dosage regimen changes if the patient requires elective surgery. Since warfarin reduces blood clotting, the risk of bleeding becomes significantly higher, therefore, a week before the planned intervention, the INR is determined, and warfarin is discontinued approximately 2-5 days depending on its level. In case of risk of thrombosis, it is replaced with heparin administered subcutaneously.

During and after surgery, the risk of thrombosis is eliminated by the administration of heparin, which is used in the postoperative period in parallel with the restoration of warfarin under strict control of coagulation.

PTI and INR, analysis directly while taking the medicine

Before prescribing Warfarin, the doctor must monitor IPT and INR:

• INR is an abbreviation for international normalized ratio, which stands for the ratio of the prothrombin time of a specifically selected person (that is, the patient) to the standard prothrombin period;
• PTI stands for prothrombin index, which allows you to compare the ratio of prothrombin time in an absolutely healthy person with the exact indicators of the selected patient.

According to the instructions, it is advisable to undergo both tests before use. The PTI norm ranges from 70-100 units. Warfarin Nycomed is able to reduce this figure to 24-26 units. It is dangerous when this parameter is higher, this indicates that the patient has a high risk of developing a stroke. If the level is too low, severe bleeding can occur, which can be fatal.

Restoring the body after an overdose

The main course of intensive therapy after an overdose of warfarin is carried out in a hospital setting. Possible procedures:

• Administration of warfirin antidote - Vikasol. Vikasol is used when the INR index is above 6 - 2 milligrams of the drug every 4 hours. If the INR value is above 10, it is rational to administer 5-10 milligrams of vitamin K intravenously;
• Plasmapheresis. Blood purification from toxic components of the drug is carried out in case of severe overdoses of warfarin. In case of severe bleeding and a very serious condition of the patient, a direct infusion of plasma is performed;
• Dropper. In severe forms of overdose, classic saline and glucose are supplemented by intravenous drip administration of substances that are protein coagulation factors;
• Support of vital signs. Symptomatic therapy and resuscitation are carried out according to standard protocols and allow you to maintain normal all basic vital signs - breathing, blood pressure, heartbeat, and other parameters.

Detailed instructions for use

To get only benefits from the medication for the body and avoid unpleasant side effects, you should follow a number of simple rules:

1. Before starting treatment, the patient must undergo an INR and PTI test. Repeated testing is carried out every 4-8 weeks, which allows you to monitor the condition of the blood. In this case, the therapy itself may already be completed.
2. Warfarin Nycomed is taken 1 time per day, strictly according to the instructions at the same time.
3. The duration of the required treatment period is determined by the doctor individually and directly depends on the severity of the disease and the general condition of the patient.
4. If the patient has previously used Warfarin, he is usually prescribed a starting dose equal to twice the maintenance dose. The course of treatment with this regimen is 2 weeks.
5. On day 5, immediately after starting to take the pills, the patient must undergo an additional INR test. Based on its results, the doctor adjusts the dosage and duration of treatment as a whole, taking into account the recommendations from the instructions.
6. When INR levels are high (2.5-3.5 units), Warfarin continues to be used only for complicated myocardial infarction and after heart valve replacement surgery.

If the patient has not previously had to deal with Warfarin, then he is prescribed an initial dosage. Usually it is 2 tablets. Primary treatment is carried out over 4 days. After passing the INR analysis, the dosage is adjusted according to the instructions from 1 to 3 tablets according to the schedule for every 24 hours.

If the INR is between 2 and 3, the prescription and subsequent use of Warfarin is permitted only for the following diagnoses:

• therapy and prevention of pulmonary embolism;
• atrophy of heart valves;
• venous thrombosis (there are contraindications in the instructions);
• prosthetics (a technique requiring surgical intervention) of the heart valve using bioprostheses;
• dilated cardiomyopathy;
• atrial fibrillation.

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. Other coumarin drugs (acenocoumarol, marcumar, marivan) can be used. The recommendations given are mostly applicable to any anticoagulant.

The purpose of prescribing this medicine is to prevent the recurrence of blood clots, which could cause a sharp deterioration in your condition or the development of 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.

The treatment prescribed to you is received by a very large number of patients all over the world. 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.

How to monitor treatment

Carrying out antithrombotic (anticoagulant) therapy can save your life and health, but requires increased attention and mandatory compliance with the doctor’s recommendations. Warfarin is a drug that reduces the ability of blood to clot, so its excess can lead to hemorrhagic complications, i.e. to bleeding. To avoid complications, the required dose of warfarin is monitored using a blood test called INR (International Normalized Ratio). This may sometimes be referred to as INR in laboratory responses. During the entire period of taking warfarin, the INR should be in the range of 2.0 - 3.0. If the INR is less than 2.0, then blood clotting is not reduced and thrombotic complications are possible. If the INR is more than 4.0, hemorrhagic complications are very real. An increase in INR from 2.5 to 4.0 indicates the need to reduce the dose of the drug, but usually does not pose a direct threat. For some diseases, the required upper limit of INR is 4.0 - 4.4.

In the absence of the ability to determine INR, monitoring by prothrombin time (PT) is acceptable, but this method is much less reliable. No other blood tests are needed to calculate your warfarin dose. To identify the side effects of the drug, a general blood test, urine test and some biochemical tests are periodically prescribed.

How to take the drug

Warfarin is available in 2.5 milligram tablets. Most often, the “starting” and “maintenance” doses of the drug are 5 milligrams (2 tablets) per day. In many cases, for more “fine” adjustments, you will change the dose of the medicine that you take not per day, but per week. This may require either dividing the tablet in half or taking different numbers of tablets on different days. To make it easier to monitor your treatment, you may be given a special account book, or you can keep a notebook with a treatment diary, where it is useful to note the doses of warfarin, INR level, and other laboratory data.

Warfarin is taken in the entire daily dose at one time, preferably at 17:00 - 19:00. Take the tablets with water. It is not recommended to take it with food, but can be taken on an empty stomach. Phenyline is usually taken in 2 doses.

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.

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.

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.

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.

What you should immediately tell your doctor about

• Black (tarry) stool color
• Pink or red urine
• Bleeding from the nose or gums (including when brushing teeth)
• Unusually heavy or prolonged menstrual bleeding
• Bruises or swelling on the body that occur for no apparent reason
• Any significant changes in well-being or health
• The appearance of skin spots on the thighs, abdominal wall, mammary glands

What to avoid

Engaging in traumatic sports where blows, bruises, and falls are possible.

Intramuscular injections. In outpatient treatment, in most cases, medications can be selected for oral administration.

Repeatedly take the medicine within one day. If you do not remember whether you took warfarin today, skip the dose.

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.

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.

Where can I get tested for INR?

INR is not some special previously unknown analysis that requires special equipment. This is a calculated indicator for which quite ordinary, but more strictly standardized reagents are needed. Therefore, determination of INR is available today to most laboratories. Take into account how long it will take to get the test result. Providing results within half an hour after blood collection is not uncommon, which greatly simplifies treatment monitoring.

Treatment with indirect anticoagulants is designed to protect your health and life. Remember that it will be easy and safe only in close cooperation with your doctor.

Material used from the website “Association of Phlebologists of Russia”: https://www.phlebo-union.ru/for-patient/varfarin.html

Taking Warfarin in old age

There are no special recommendations for elderly patients when using Warfarin. But treatment with this drug should be carried out exclusively under the constant supervision of the treating doctor and in compliance with the instructions, since with age the risk of developing various side effects increases significantly.

The instructions indicate that when used simultaneously with anticholinergic drugs, memory impairment and absent-mindedness may occur. And when combined with hypoglycemic drugs, the effect of the latter is enhanced.

Contraindications

Warfarin is not prescribed in case of individual high sensitivity to the components, pregnancy, as well as in the following diseases:

• severe liver pathology;
• insufficiency of the filtering function of the kidneys;
• low blood platelet count;
• intravascular coagulation (DIC syndrome);
• increased risk of bleeding;
• dilation of the esophageal veins;
• vessel aneurysm;
• peptic ulcer;
• wounds, injuries, postoperative wounds;
• endocarditis due to bacterial infection;
• hypertension with a malignant course and poor response to medications;
• suspected cerebral hemorrhage, hemorrhagic stroke.

Recommendations for patients with renal and liver failure

There are no special contraindications or recommendations in the instructions for use for patients with renal failure. Even if a person is on peritoneal dialysis, he should not increase the dose of the drug without additional advice from a doctor.

With liver failure and other liver problems, patients experience increased sensitivity of the body to Warfarin. Before taking the drug, you should consult your doctor. It is the liver that metabolizes Warfarin, and it, in turn, has a direct effect on the level of blood clotting. Therefore, people with liver failure should strictly monitor their INR.

Overdose and its treatment

If the dose of the drug is exceeded or if there is a high sensitivity to it, the risk of blood loss increases many times. Conditions that increase the likelihood of this complication include:

• age after 60 years;
• anemia;
• malignant neoplasms;
• injuries;
• INR is high, exceeds the target level;
• in the past the patient suffered from a cerebral hemorrhage or perforation of an ulcer;
• liver and kidney diseases;
• taking other medications that reduce the coagulating properties of blood;
• alcohol abuse;
• arterial hypertension without proper treatment or with drug resistance.

The intensity of bleeding ranges from the appearance of red blood cells in the urine and increased trauma to the gums to intense, life-threatening conditions. In the first cases, discontinuation of the drug is sufficient.

Large doses of vitamin K should be avoided if it is necessary to continue treatment with Warfarin in the future. It is also taken into account that partial elimination of the drug requires at least 3 days, so the effectiveness of measures to stop bleeding appears after a while.

Warfarin and pregnancy

According to the instructions for use, Warfarin quickly penetrates (almost in pure form) through the placenta and causes a teratogenic effect on the developing fetus. This leads to the development of the so-called warfarin syndrome at approximately 6-12 weeks from the start of pregnancy. Its manifestations include:

• atrophy (partial or complete death) of the optic nerve;
• nasal hypoplasia (deformation of cartilage tissue progressing in the fetus, for example, a saddle-shaped nose);
• inhibition of mental or physical development;
• punctate chondrodysplasia (visible during X-ray examination, develops in the spine and even sometimes in long bones);
• short hands and fingers;
• cataracts with the risk of partial or even complete blindness;
• microcephaly;
• fetal death.

Warfarin causes increased bleeding, which is very dangerous in the prenatal period and directly during childbirth. During lactation, the medicine is excreted along with breast milk, but in extreme cases its use is allowed when prescribed by a doctor. There is no data on the effect of the drug on fertility.

Warfarin has a number of side effects - be careful with dosage

pharmachologic effect

warfarin formula

Warfarin is included in the list of indirect anticoagulants. It blocks the activity of the enzyme necessary for the formation of vitamin K, which, in turn, helps the synthesis of individual coagulation factors - II, VII, IX, X, as well as some proteins. As a result of the drug's action, the vitamin K-dependent pathway for the production of coagulation factors is disrupted, and the higher the dosage, the more pronounced the inhibitory effect of warfarin on hemostasis.

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Warfarin does not act directly on a blood clot and, moreover, does not restore tissue in areas of ischemic damage, but its administration is necessary to ensure that there is no increase in the volume of thrombotic deposits or the detachment of their fragments with the development of embolism.

The drug is taken orally, after which it is almost completely absorbed in the intestine, and already in the first four hours after consuming the anticoagulant, its maximum amount is found in the blood, associated with plasma carrier proteins. The drug is able to pass through the placental barrier, after which its concentration in the fetal blood becomes almost the same as in a pregnant woman, but does not penetrate into breast milk.

Active warfarin from the blood enters hepatocytes, where it is inactivated. The end products of drug metabolism enter the urine through the renal filter and are excreted from the body. In addition, some of the inactive components may be excreted in the bile.

Pregnant women should not be prescribed warfarin, as it penetrates into the bloodstream of the developing fetus, reaching a therapeutic “adult” dose, which can lead to bleeding. In addition, some studies indicate a teratogenic effect of the anticoagulant. It practically does not penetrate into breast milk, but experts advise babies feeding from a mother being treated with warfarin to determine the INR. If it is necessary to use high dosages of the drug, it is advisable to stop breastfeeding.

In case of kidney failure, the effect of the anticoagulant practically does not change, which is associated with the excretion in the urine of an already inactivated drug, the circulation of which in the blood does not cause coagulation disorders. This circumstance is associated with the prescription of the same dose of the drug for renal failure as for all other patients.

Unlike the kidneys, the liver can reverse the effects of warfarin. Thus, hepatocyte deficiency increases the concentration of active forms of the drug and the formation of natural anticoagulants, which inevitably leads to an increase in the effect of the drug, so patients with pathology of the hepatic parenchyma may need to reduce the dosage of warfarin.

The route of administration of the drug is not critical for maintaining the required concentration of the drug and obtaining a therapeutic effect. Both when administered intravenously and when tablets are taken orally, an equal amount of its active forms circulates in the blood. Intravenous administration allows you to quickly achieve the maximum concentration of warfarin in plasma, but the anticoagulant effect in both cases will not occur earlier than after 3-4 days.

When it enters the body, Warfarin begins to block the processes that lead to blood clotting; it reduces the concentration of substances involved in this process in the plasma, which is why blood clotting slows down significantly.

The effect of the drug on the body begins to be felt in the period from 36 to 72 hours after administration, and after 6 days the maximum effect of the drug is noted. The active ingredients are easily absorbed through the digestive system, the metabolic process takes place in the liver.

All inactive metabolites are excreted along with bile; the metabolites are reabsorbed by the digestive system, excreted in the urine.

When taking Warfarin, you need to know that not all medications can be combined with it. The point is that some substances contained in other medications can enhance or weaken the effect of this drug, which in one way or another can lead to disturbances in the functioning of the body.

The use of Warfarin with NSAIDs increases the risk of bleeding

Let's look at the main drugs and interactions with warfarin:

• if you simultaneously take Warfarin and non-steroidal anti-inflammatory drugs, acetylsalicylic acid and penicillin antibiotics, you can cause bleeding since all these drugs have blood thinning properties, and everything should be in moderation so as not to harm health
• Warfarin should not be combined with inhibitory drugs, cimetidine, for example
• There are a number of drugs that reduce the effects of Warfarin, thereby making it practically useless: Cholestyramine, Bosentan, Mesalazine, Dicloxacillin, Nafcillin, Griseofulvin, Phenazone, Chlordiazepoxide
• There are also a number of drugs that can enhance the effect of Warfarin, thereby provoking bleeding due to excessive blood fluid: Abciximab, Cimetidine, Ethacrynic acid, Propafenone, Digoxin, Steroid hormones

If the patient is taking any medicinal or non-medicinal drugs. For example, dietary supplements, then you must definitely warn the doctor who will prescribe the drug about this.

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In this case, there are several options. In the first option, the use of a drug that can enhance, weaken or impair the absorption of warfarin is discontinued. In the second option, warfarin can be replaced with an analog drug that prevents the formation of blood clots, but has a different composition that is combined with the drug that the patient uses.

In the end, it should be noted that the heart is the main organ, without which no system can function. The heart muscle pumps blood, which carries oxygen and all necessary substances throughout the body through the vessels. If a blood clot, blockage or some other obstruction appears, blood circulation is disrupted, which results in a number of pathological processes leading to various diseases.

To avoid blood clots and blockages, you need to take medications that have a thinning effect. One of these is Warfarin, which partially absorbs vitamin K and helps control blood thickness. So as not to harm your health. You cannot self-medicate, but you should undergo an examination and consultation with a phlebologist or cardiologist.

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How safe is the drug for children?

Detailed information regarding the use of Warfarin in childhood based on practical studies is not available. But if the result justifies the means, and there are no problems with liver function, then the drug can be prescribed to the child. At the same time, he must receive proper nutrition; the diet is developed individually.

Before use, it is important to correctly calculate the dosage. Initially, it should not exceed the parameters of 0.2 mg/kg body weight. In case of viral lesions and functional disorders of the liver, the dosage is reduced by 2 times. To calculate the amount of the drug during the maintenance period, INR values ​​are used.

Treatment tactics in case of overdose

When prescribing Warfarin, it is necessary to monitor blood coagulation function. For this purpose, regular assessment of the coagulogram should be carried out, in particular the prothrombin index and prothrombin time. The latter should be kept at a level of up to 5%. Moreover, if these indicators are outside the normal range, then the medicine should be discontinued.

In the event of bleeding during an overdose, the main antagonist of warfarin, vitamin K, must be immediately administered, which will restore blood coagulation activity.

By ensuring that the reduced form of this substance enters the body, it is possible to restore the synthesis of normal coagulation factors and improve the rheological state of the blood. Please remember that this may take some time.

Conventional hemostatic therapy is ineffective, but it is still necessary to use it.

Side effects

Depending on the age, build and other characteristics of the human body, the following side effects may be observed after taking the drug:

• blood observed in urine;
• problems with the gastrointestinal tract - diarrhea, prolonged constipation, nausea, dull pain in the stomach;
• allergic reactions - itching and rashes on the skin, anemia, age spots, eosinophilia, jaundice, a rash similar to seasonal allergies, urticaria;
• increased body temperature - the patient must be given an antipyretic drug and immediately consult a doctor;
• bruises under the skin - stop using the drug and immediately consult an experienced doctor;
• tissue necrosis;
• slight hair loss;
• kidney problems - nephritis.

Side effects of Warfarin

Due to the use of Warfarin, side effects may include the following:

• hematomas, bleeding, tissue necrosis due to local thrombosis, anemia;
• rashes, dermatitis, hair loss;
• nausea, abdominal pain, jaundice, diarrhea, hepatitis, vomiting, increased activity of liver enzymes, cholestasis;
• paresthesia (sensitivity disorder), purple coloring of the toes, feeling of cold, vasculitis (inflammation of the walls of blood vessels);
• taste disturbance, headache, asthenia, dizziness, increased fatigue;
• skin rash, fever, itching, swelling and hives.

Also, side effects of Warfarin sometimes manifest themselves in the form of symptoms such as spots on the skin, bruises, and swelling, which can be localized in various areas.

Diet while using Warfarin

According to recent studies, plants of the cabbage family are very rich in vitamin K. It is its excess that affects INR levels and reduces the effectiveness of Warfarin. But at the same time, if your daily food does not contain vitamin K at all, this can lead to bleeding. This is why a balanced diet and strict adherence to the diet are so important for the entire period of treatment and use of the drug.

It is advisable to exclude all green foods. The greatest amount of vitamin K contains:

• lettuce;
• avocado is a tropical fruit with a large seed, suitable for salads, and has a nutty flavor;
• chayo leaf;
• coriander – the seeds of cilantro, which is very popular in Georgian and Armenian cuisine;
• chicory is a well-known coffee substitute;
• green mustard;
• parsley – very useful for men’s health and potency;
• pistachios - you should not buy salted ones, which are produced as a snack for beer;
• spinach greens - vitamins are contained only in fresh greens, frozen is suitable for consumption in this case;
• soya beans;
• Brussels sprouts;
• turnip greens;
• broccoli and classic cabbage;
• onion;
• cucumbers – the largest amount of vitamin is contained in the peel;
• kiwi is a fragrant and tasty fruit;
• mint - do not overuse, it is a powerful sedative;
• olive oil – can be used for salad dressing and frying;
• amaranth greens;
• young peas;
• red seaweed;
• watercress.

Along with useful products, there are also dangerous ones, such that they can significantly increase the risk of bleeding and even lead to death if they are used simultaneously while using Warfarin. And although the instructions for the drug do not contain such contraindications, it is recommended to refrain from eating the following berries and plants:

• currant;
• anise;
• ginger and garlic;
• echinacea and ginseng;
• cordyceps;
• wort;
• fish fat;
• rose hip;
• lingonberries, strawberries and cranberries;
• dandelions;
• grapefruit;
• gingko biloba and chamomile;
• horse chestnut;
• cherries.

When purchasing a product in a store, do not forget to study the label, which indicates its composition. Particular attention should be paid to searching the list for vitamin K. It is often found in processed foods and carbonated sweet drinks or juices (berry ones are especially dangerous). For example, you can drink no more than 1 glass (200 ml) of cranberry juice per day.

First aid for overdose

In case of an overdose of warfarin, the victim must be provided with first aid, simultaneously calling a medical team - with a high degree of probability, the patient, after examination, will be sent to the nearest hospital for monitoring, intensive care, and possibly resuscitation (in case of severe overdose).

Standard actions may include:

• Gastric lavage and induction of vomiting. The procedure is relevant in the first hours after an overdose, when complete absorption of the drug into the bloodstream has not yet occurred. The victim, if he is conscious and all reflexes are preserved, is given 1-2 liters of water to drink, after which pressure is applied to the root of the tongue. If necessary, the event is repeated several times;
• Sorbents. The dosage regimen is 10-30 grams of adsorbent substance per single dose, which should be washed down with a small amount of water. Typical preparations are activated carbon, Polysorb, Smecta;
• Waiting for the ambulance to arrive. Before the medical team arrives, the victim is placed in a horizontal position on his side, with a cushion made from available materials or a pillow placed under his head. The patient's vital signs are monitored - his breathing, heartbeat and pulse, and, if necessary, manual resuscitation procedures are performed;
• Antidote. A direct antidote to warfarin is vikasol or vitamin K. It restores coagulant activity and can usually be used in cases of moderate or severe overdose, but with mandatory monitoring of the INR index (INR), which significantly complicates its use in “field” conditions. In case of prolonged absence of qualified medical care, taking into account the risks of thrombosis, Vicasol can be administered intravenously or orally at a dosage of 5-10 milligrams.

Interaction with other medications

What indications Warfarin has can be read in more detail in the instructions itself, but before that you need to thoroughly understand whether it interacts with other medications. For convenience, we offer sorting of medications that can become active and conflict with Warfarin into groups:

1. Antibiotics of general and targeted action - Ciprofloxacin (Ciproxin), it is very dangerous to use Erythromycin, Metronidazole (Flagyl) during this period; Sulfamethoxazole with Trimethoprim (Bactrim) is rarely prescribed.
2. Medicines whose action is aimed at normalizing heart function and reducing the level of bad cholesterol - Aspirin, Clopidogrel (Plavix), Amiodarone (Cordarone), the most popular in Europe are Simvastatin (Zukor) and its analog Fenofibrate.
3. Antidepressants - Fluoxetine (Prozac), Fluvoxamine (Fevarin), Paroxetine has a calming effect.
4. Hormones similar to those secreted by the thyroid gland, the most common is Thyroxine.
5. Antiviral and antipyretic drugs – Paracetamol.
6. Anti-inflammatory (including colds) and painkillers (especially those used to treat arthritis) - most often prescribed are Aspirin, Meloxicam (Mobis) or their analogue Celecoxib; pharmacies usually recommend Ibuprofen (Nurofen), Indomethacin (Indocid), Methyl salicylate (Deep Hit Ointment) or the most budget option - Paracetamol (Panadol).
7. Antiulcer drugs - Esomeprazole (Nexium), especially dangerous Cimetidine (Tagamet), Omeprazole.
8. Corticosteroids – Prednisolone.
9. Antiepileptic drugs – Carbamazepine (Tegretol).
10. Antifungal drugs - Miconazole (Daktarin), analogues can be considered Fluconazole (Diflucan), Griseofulvin.

Drug action

The drug is an anticoagulant with an indirect effect. Warfarin stops the formation of special clotting factors produced in the liver. In particular, the formation of factors that depend on the level of vitamin K is inhibited. When their content in the blood is low, the rate of coagulation fades.

The anticoagulant effect begins 1.5-3 days after the start of the drug. The maximum effect is noticeable within a week. After the last dose, the medicine lasts for another 4-5 days.

Special Recommendations

Warfarin therapy is necessarily accompanied by special recommendations that should be followed.

Warfarin and alcohol interact with each other. Usually, alcoholic drinks suppress the effect of medications, but in the case of Warfarin they only enhance its effect on the structure of the blood. During treatment, drinking alcohol is acceptable, but only in doses that will not lead to serious consequences.

If it is necessary to receive painkillers, patients are prescribed opiates, tramadol and paracetamol.

Other precautions

You must understand that you are contraindicated from engaging in traumatic sports. Intramuscular injections should also be avoided (if they can be avoided).

You should know that you are taking a drug that saves your life and maintains your health, and the effectiveness of Warfarin depends, among other things, on you.

Trips

Be sure to take an adequate supply of Warfarin with you and check your INR before leaving. Don't forget about your diet - when traveling, food often differs significantly from usual, and this can affect your INR levels.

Alcohol

Alcohol, by affecting the liver, enhances the effect of Warfarin. In addition, even small doses of alcohol impair coordination and increase the risk of accidental injury, which can be life-threatening in a person taking Warfarin.

Pregnancy

It is equally important to understand that taking Warfarin requires a more careful approach to pregnancy planning; in the case of an unplanned pregnancy, discuss with your doctor the switch to the use of low molecular weight heparins.

Warfarin is extremely harmful to the fetus, so if you are planning a pregnancy, discuss this with your doctor.

INR control

To monitor the INR, you must contact a laboratory capable of conducting this study.

You can consider purchasing a CoaguChek XS or qLabs® ElectroMeter as an option. It is convenient, the devices are easy to use.

However, at a price of 30 - 40 thousand rubles per device, and with the price of a test strip comparable to the price of a laboratory test, purchasing the device is not economically feasible. You have to choose between convenience and savings.

History of the creation of Warfarin

Luck smiled on Carl Link; in 1936 he discovered dicumarol, a product of the oxidation of coumarin.
Warfarin was first registered as a rodent poison in the United States in 1948 and immediately became popular. Name "Warfarin "

) comes from the abbreviation
WARF
(English
W
isconsin
A
lumni
Research
Foundation

) + the ending
-arin
indicating a connection with coumarin.

But the toxic properties of the new substance were not confirmed, and research in the fifties of the twentieth century aroused the interest of clinicians in the drug. Since then, Warfarin has saved thousands of lives.

One of the first famous people to receive Warfarin was US President Dwight Eisenhower.

Combination with other medications

Should Warfarin be combined with other medications or not? The issue is resolved after a medical consultation.

Combination with pharmaceuticals that affect platelet counts sometimes leads to a significant risk of internal hemorrhage. These substances include Aspirin, Dipyridamole, Penicillin, Non-steroidal anti-inflammatory drugs.

Bleeding may occur when an anticoagulant and a cytochrome inhibitor are used together. Some medications and herbs can increase or decrease the effectiveness of Warfarin, so consulting a doctor before combining medications is mandatory.

It is not recommended to combine Warfarin and drugs containing St. John's wort. The effect of the medicine may decrease if you simultaneously start using foods rich in vitamin K. A lack of this vitamin and the use of a laxative lead to an increase in the beneficial effect of the medicine.

Analogues of the drug

Until 2011, Warfarin Canon was the only anticoagulant drug that had an effect on blood composition. Then Xarelto, an alternative drug to rivaroxaban, was approved for sale. Which drug is better, warfarin or xarelto?

Disadvantages of Warfarin

• can be combined with a limited number of drugs;
• the need for regular testing of prothrombin time, on the basis of which the dose is adjusted for each patient;
• regular monitoring of the patient's condition;
• incompatibility with many products that contain vitamin K.

Benefits of Xarelto

• minimal interaction with other medications and food. There is no need to discontinue any drug while taking them simultaneously. There is also no question of constant monitoring of body parameters;
• dosage adjustment is rarely required, there are no dietary restrictions;
• Xarelto and Warfarin are almost equally likely to cause bleeding. But Xarelto provokes less cerebral hemorrhages;
• Taking Xarelto leads to fewer clotting problems in the postoperative phase.

Warfarin Nycomed, if necessary, is replaced with similar drugs that have similar pharmacological effects. Among these drugs, the most popular are Warfarex and Xarelto.

A remedy of identical action is prescribed by a specialist. Changing the medication on your own can lead to undesirable consequences.

Warfarin cost: from 61 rub.

Cost of Xarelto: from 1452 rubles.

Table comparing drug analogues by cost. Data was last updated on 09/14/2020 00:05.