This grade answers one narrow question: how strong is the public evidence and safety record behind this drug, and how clean is its money trail and court record? It is not a verdict on whether the drug is right for you.
WARNING: BLEEDING RISK Warfarin sodium can cause major or fatal bleeding [see Warnings and Precautions (5.1) ]. Perform regular monitoring of INR in all treated patients [see Dosage and Administration (2.1) ]. Drugs, dietary changes, and other factors affect INR levels achieved with warfarin sodium therapy [see Drug Interactions (7) ]. Instruct patients about prevention measures to minimize risk of bleeding and to report signs and symptoms of bleeding [see Patient Counseling Information (17) ]. WARNING: BLEEDING RISK See full prescribing information for complete boxed warning. Warfarin sodium can cause major or fatal bleeding. ( 5.1 ) Perform regular monitoring of INR in all treated patients. ( 2.1 ) Drugs, dietary changes, and other factors affect INR levels achieved with warfarin sodium therapy. ( 7 ) Instruct patients about prevention measures to minimize risk of bleeding and to report signs and symptoms of bleeding. ( 17 )
Warnings the FDA chose to announce publicly after approval, as opposed to quiet label edits. Class-wide items name the drug's class, not this drug specifically.
Listed on the WHO Model List of Essential Medicines: a global expert panel judged it among the medicines a health system should always have, on evidence of value, not marketing.
Warfarin sodium tablets, USP are indicated for: Prophylaxis and treatment of venous thrombosis and its extension, pulmonary embolism (PE). Prophylaxis and treatment of thromboembolic complications associated with atrial fibrillation (AF) and/or cardiac valve replacement. Reduction in the risk of death, recurrent myocardial infarction (MI), and thromboembolic events such as stroke or systemic embolization after myocardial infarction. Warfarin sodium is a vitamin K antagonist indicated for: Prophylaxis and treatment of venous thrombosis and its extension, pulmonary embolism ( 1 ) Prophylaxis and treatment of thromboembolic complications associated with atrial fibrillation and/or cardiac valve replacement ( 1 ) Reduction in the risk of death, recurrent myocardial infarction, and thromboembolic events such as stroke or systemic embolization after myocardial infarction ( 1 ) Limitations of Use Warfarin sodium has no direct effect on an established thrombus, nor does it reverse ischemic tissue damage. ( 1 ) Limitations of Use Warfarin sodium has no direct effect on an established thrombus, nor does it reverse ischemic tissue damage. Once a thrombus has occurred, however, the goals of ant...
Warfarin sodium tablets, USP are contraindicated in: Pregnancy Warfarin sodium tablets, USP are contraindicated in women who are pregnant except in pregnant women with mechanical heart valves, who are at high risk of thromboembolism [see Warnings and Precautions (5.7) and Use in Specific Populations (8.1) ]. Warfarin sodium can cause fetal harm when administered to a pregnant woman. Warfarin sodium exposure during pregnancy causes a recognized pattern of major congenital malformations (warfarin embryopathy and fetotoxicity), fatal fetal hemorrhage, and an increased risk of spontaneous abortion and fetal mortality. If warfarin sodium is used during pregnancy or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to a fetus [see Use in Specific Populations (8.1) ]. Warfarin sodium tablets, USP are contraindicated in patients with: Hemorrhagic tendencies or blood dyscrasias Recent or contemplated surgery of the central nervous system or eye, or traumatic surgery resulting in large open surfaces [see Warnings and Precautions (5.8) ] Bleeding tendencies associated with: Active ulceration or overt bleeding of the gastrointestinal...
Tissue necrosis: Necrosis or gangrene of skin or other tissues can occur, with severe cases requiring debridement or amputation. Discontinue warfarin sodium and consider alternative anticoagulants if necessary. ( 5.2 ) Calciphylaxis: Fatal and serious cases have occurred. Discontinue warfarin sodium and consider alternative anticoagulation therapy. ( 5.3 ) Acute kidney injury may occur during episodes of excessive anticoagulation and hematuria. ( 5.4 ) Systemic atheroemboli and cholesterol microemboli: Some cases have progressed to necrosis or death. Discontinue warfarin sodium if such emboli occur. ( 5.5 ) Heparin-induced thrombocytopenia (HIT): Initial therapy with warfarin sodium in HIT has resulted in cases of amputation and death. Warfarin sodium may be considered after platelet count has normalized. ( 5.6 ) Pregnant women with mechanical heart valves: Warfarin sodium may cause fetal harm; however, the benefits may outweigh the risks. ( 5.7 ) 5.1 Hemorrhage Warfarin sodium can cause major or fatal bleeding. Bleeding is more likely to occur within the first month. Risk factors for bleeding include high intensity of anticoagulation (INR >4.0), age greater than or equal to 65, hi...
The following serious adverse reactions to warfarin sodium are discussed in greater detail in other sections of the labeling: Hemorrhage [see Boxed Warning , Warnings and Precautions (5.1) , and Overdosage (10) ] Tissue Necrosis [see Warnings and Precautions (5.2) ] Calciphylaxis [see Warnings and Precautions (5.3) ] Acute Kidney Injury [see Warnings and Precautions (5.4) ] Systemic Atheroemboli and Cholesterol Microemboli [see Warnings and Precautions (5.5) ] Limb Ischemia, Necrosis, and Gangrene in Patients with HIT and HITTS [see Warnings and Precautions (5.6) ] Other Clinical Settings with Increased Risks [see Warnings and Precautions (5.8) ] Other adverse reactions to warfarin sodium include: Immune system disorders: hypersensitivity/allergic reactions (including urticaria and anaphylactic reactions) Vascular disorders: vasculitis Hepatobiliary disorders: hepatitis, elevated liver enzymes. Cholestatic hepatitis has been associated with concomitant administration of warfarin sodium and ticlopidine. Gastrointestinal disorders: nausea, vomiting, diarrhea, taste perversion, abdominal pain, flatulence, bloating Skin disorders: rash, dermatitis (including bullous eruptions), pruritu...
Dosage and Administration, Renal Impairment ( 2.5 ) 5/2017 Warnings and Precautions, Calciphylaxis ( 5.3 ) 9/2016 Warnings and Precautions, Acute kidney injury ( 5.4 ) 5/2017
Source: FDA SPL label for Warfarin Sodium (Aphena Pharma Solutions - Tennessee, LLC), effective 20210729. Full label on DailyMed.
These are counts of reports people filed, not rates of harm. Anyone can file one, and nobody checks whether the drug was the cause. Millions of doses are taken for every report sent, so the useful part is how this drug compares with the average across all drugs.
| 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
|---|---|---|---|---|---|---|---|
| 14,119 | 11,861 | 8,118 | 5,653 | 4,708 | 4,105 | 3,461 | 1,479 |
1,727 reports blaming this drug for every million Medicare prescriptions filled, which is 0.6× the typical drug on this site. (8,695 reports in 2024–2026, against 5,034,389 Medicare fills in one year. This is the one number here that accounts for how many people take the drug.)
Source: the FDA's Adverse Event Reporting System (FAERS). Reports are voluntary and unverified. Drugs that are prescribed a lot, in the news, or in lawsuits attract more reports, so the percentages are compared with the whole database to correct for that partly, not fully.
| Date | Class | Firm | Reason |
|---|---|---|---|
| 01/2022 | Class II | CARDINAL HEALTHCARE | CGMP Deviations: Products were exposed to temperatures outside of the products labeled storage conditions. |
| 01/2022 | Class II | CARDINAL HEALTHCARE | CGMP Deviations: Products were exposed to temperatures outside of the products labeled storage conditions. |
| 08/2014 | Class III | Taro Pharmaceuticals U.S.A., Inc. | Failed Content Uniformity Specifications. |
Class I = reasonable probability of serious harm. Class II = temporary or reversible harm. Class III = unlikely to harm. Most generic recalls are manufacturing or labeling defects for one lot, not a verdict on the molecule.
Counts measure how much evidence exists and how transparent it is, not how big the benefit is. For that, ask your prescriber: if 100 people like me took this, how many would get better because of it, and how many would be harmed? (Doctors call these the "number needed to treat" and "number needed to harm.") It differs by condition and is the number drug ads leave out. Sources: PubMed, ClinicalTrials.gov.
In 2024, drug companies reported $0 in payments to US physicians and hospitals tied to this drug across 0 transactions.
No pending federal MDL names this drug or its brands.
Not named in any federal pharmaceutical settlement of $100M or more on record.
Sources: CMS Open Payments (Sunshine Act); Judicial Panel on Multidistrict Litigation pending docket list; DOJ settlements as tabulated on Wikipedia with links to the primary record. State-court and individual suits are not included.
| Product | Fills | $/fill |
|---|---|---|
| Warfarin Sodium | 4,665,402 | $9 |
| Jantoven | 368,987 | $9 |
Same ATC pharmacological class, graded ones first, best grade at the top. Being in the same class does not make them interchangeable for your condition; it makes them worth asking about.