Warfarin
Also sold as Warfarin Sodium
Medicine summary · from official FDA labels · Oct 19, 2026
What it’s used for
Warfarin sodium tablets 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.
How to take it
Individualize dosing regimen for each patient, and adjust based on INR response. (2.
Important warnings
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.
Common side effects
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.
Interactions
Concomitant use of drugs that increase bleeding risk, antibiotics, antifungals, botanical (herbal) products, and inhibitors and inducers of CYP2C9, 1A2, or 3A4.
Forms & strengths
1 MG Oral Tablet · 10 MG Oral Tablet · 2 MG Oral Tablet · 2.5 MG Oral Tablet · 3 MG Oral Tablet · 4 MG Oral Tablet · 5 MG Oral Tablet · 6 MG Oral Tablet · 7.5 MG Oral Tablet · 0.5 MG Oral Tablet
Questions to ask your doctor or pharmacist
- Is this the right medicine for my condition, and how long should I take it?
- What side effects should I watch for, and which need urgent attention?
- Does this interact with my other medicines, supplements, or alcohol?
- What should I do if I miss a dose or take too much?