Leiden's warfarin dose 5 to 10 percent (e
Assessing the response is complicated by a delay of 2–3 days before the INR reflects any changes in warfarin dose
Role in therapy The use of warfarin is declining with preference now being given to direct oral anticoagulants (DOACs) as first-line therapy in common anticoagulation indications, such as VTE treatment and prevention of recurrence, and stroke prevention in non-valvular atrial fibrillation (NVAF)
0 Our warfarin calculator will not only tell you how to deal with the decreased or increased INR — it'll also leave you with life-saving recommendations that can be used in the event of massive bleeding in patients on warfarin
Warfarin Dosage Medically reviewed by Drugs
5 mg; 3 mg; 6 mg Usual Adult Dose for: Prevention of Thromboembolism in Atrial Fibrillation Thromboembolic Stroke Prophylaxis Myocardial Infarction Myocardial Infarction - Prophylaxis Dose Adjustments Always take into account potential reasons for elevated and subtherapeutic INRs
Warfarin (brand name: Jantoven) is a prescription medication that interferes with normal blood clotting (coagulation)
If the INR is too low, blood clots will not be prevented, but if the INR is too high, there is an increased risk of bleeding
For each out-of-range INR value, attempt to identify the cause
1 - 4
The typical starting dose of warfarin in adults is 2 mg to 5 mg once daily
Current INR: (for patients previously on warfarin) • An INR reported on the same calendar date as the scheduled warfarin dose
2
4 units per day should result in a dose reduction (otherwise an INR overshoot is likely)
The first of these was a clinical algorithm that provides clear warfarin dosing rules based on INR thresholds: if INR is less than 1
Once the maintenance dose is stabilized in the therapeutic range, it is rarely necessary to alter it
Recent studies confirmed the importance of initiating warfarin therapy with lower doses (eg 5mg) as opposed to older protocols which advocated higher initial dosages (7
The prescriber should enlist the services of a pharmacist to help "dial in" the warfarin dose, and inpatients often have their INR and dose adjustment handled by a pharmacist
0 (no bleeding) Cease warfarin Administer phytomenadione (Vitamin K) 1 mg
g
Assessing the response is complicated by a delay of 2-3 days before the INR reflects any changes in warfarin dose
Your warfarin dose is then adjusted in order to maintain therapeutic INR (international normalized ratio) levels, The laboratory measure INR is used to determine your coagulation status, which is needed in order to adjust your dosage of warfarin
Starting, stopping or changing the dose of an interacting drug: check INR in 4‐6 days after the change
Give phytomenadione (vitamin K#) 5 to 10 mg IV, FFP 150 to 300 mL and PCC (refer to Anticoagulant Guideline for Hospitalised Adult Patients, Table 53)
Warfarin can be challenging to manage due to its narrow therapeutic range, variable dose-response among patients and common interactions with drugs, diet, alcohol, and other factors
Current indication for warfarin, INR goal, warfarin dosing and any planned warfarin boost doses iii
It can also be used to assess the risk of bleeding or the coagulation status of the patients
1 5mg/day-1
3 < 1
Dosing of warfarin is discussed in detail separately
The duration of treatment is based on the indication as follows: For patients with a DVT or PE secondary to a transient (reversible) risk factor, treatment with warfarin for 3 months is recommended
Warfarin should be dosed to achieve the target INR for a specific indication
If you're taking warfarin, you will need regular blood tests to check how quickly your blood clots
When your first dose of warfarin is prescribed, it doesn't matter how For oral dosage form (tablets): For prevention or treatment of blood clots: Adult—At first, 2 to 5 milligrams (mg) as a single dose once per day
18, 19 Concurrent therapy with medications such as non overlap is required 10,11 regardless of initial dosing; i
Venous Thrombosis
CBC should have a baseline result with rechecking a minimum of every 3 days thereafter
425 x BSA in m) - (0
-1639G>A variant is used in this table
If you're due for a blood test, write any new information on your Warfarin is an oral medication administered once daily
However, there All of the adjustments we make to warfarin therapy are based on the weekly dose
Safe warfarin prescribing requires understanding its mechanism of action, indications, contraindications, treatment targets, duration of treatment, dosing, international normalised ratio (INR) monitoring, reversal and interactions
Full Guideline: Warfarin Management - Adult - Inpatient Guideline Overview • Target INR and duration of therapy are based on indication for warfarin use- see full guideline • Risk factors which alter sensitivity to warfarin • Monitoring considerations • Warfarin dosing protocol with INR goal 2-3 • Warfarin dosing protocol with INR Adjust the warfarin dose to maintain a target INR of 2
• The international normalised ratio (INR) is used to monitor patients receiving warfarin
By inhibiting CYP2C9 (and a little CYP3A4), fluconazole significantly increases the action of warfarin
0 >8
80 mg with food for first dose, then 40 mg per day with food for 35 to 42 days Avoid use with P-glycoprotein inhibitors and CrCl < 30 mL per minute per 1
Your warfarin dosage will depend on your INR results
1 – 3
Warfarin, a vitamin K antagonist, is an oral anticoagulant indicated for the prevention and treatment of venous thrombosis and its extension and the prevention and
If dose adjusted by 10-20%, starting or stopping an interacting medication, change
Good INR control, defined empirically as a TTR >60%, may be best achieved by appropriately addressing both high and low INR values using a consistent
Background: The influence of child characteristics on warfarin dosing has been reported; however, there is no consensus on the nature and extent of
A: Baseline CBC, PT/INR required prior to continuation of warfarin therapy
Children—Use and dose must be determined by your doctor
The typical starting dose of warfarin in adults is 2 mg to 5 mg once daily
2
The warfarin dosing calculator estimates the warfarin maintenance dose based on patient data (weight and height for body surface area), target INR for control over coagulation and based on other bleeding risk factors such as (DVT or PE present or smoking)
The effect of warfarin has great inter- and intra-individual variation based on a variety of genetic, dietary, and medication effects
5-3
0 but Less than 10
The tablets and the boxes they come in are different colours to make it easier for you to take the right dose
5 3 mg 2
Indications for use, INR goals and duration of therapy are listed in Table 1 1
Dosing of warfarin is discussed in detail separately
You will need frequent "INR" or prothrombin time tests (to measure your blood-clotting time and determine your warfarin dose)
157 Control was similar with the computer-guided and empirical dose adjustments in the INR range of 2
0
Several brands of warfarin exist, including Coumadin, Marevan, and many more internationally
25mg/day 1
Warfarin dose changes: check INR weekly until stable
Full Guideline: Warfarin Management - Adult - Inpatient Guideline Overview • Target INR and duration of therapy are based on indication for warfarin use- see full guideline • Risk factors which alter sensitivity to warfarin • Monitoring considerations • Warfarin dosing protocol with INR goal 2-3 • Warfarin dosing protocol with INR A baseline INR must be resulted prior to the verification of the first dose of warfarin