WARFARIN SODIUM FDA MedWatch Direct Reports Summary

These tables and charts are created from 733 voluntary U.S. reports for WARFARIN SODIUM (WARFARIN SODIUM) reported by individuals to the FDA via the MedWatch Reporting System from 2004 through April 28, 2026.

For a summary of adverse events including mandatory reports submitted by pharmaceutical companies (all countries and all reporter types) to the FAERS database, View FDA FAERS WARFARIN SODIUM Report.

Top Adverse Effects Associated with WARFARIN SODIUM (from U.S. FDA Medwatch Reports)

	Side Effect	# of FDA Reports
1	BLEEDING	130
2	INTERNATIONAL NORMALISED RATIO INCREASED	104
3	GASTROINTESTINAL BLEEDING	89
4	ANEMIA	61
5	HAEMOGLOBIN DECREASED	51
6	FALL	39
7	GASTRIC HAEMORRHAGE	35
8	ANTICOAGULATION DRUG LEVEL ABOVE THERAPEUTIC	34
9	CEREBRAL HAEMORRHAGE	30
10	THERAPY INTERRUPTED	30
11	DEATH	28
12	BRUISING	27
13	DIARRHEA	24
14	LACK OF STRENGTH AND ENERGY (ASTHENIA)	23
15	STROKE	23
16	FATIGUE	23
17	BLOOD IN URINE	23
18	BRAIN INJURY	22
19	DIZZINESS	20
20	INTERNATIONAL NORMALISED RATIO ABNORMAL	20
21	HEADACHE	19
22	ANTICOAGULATION DRUG LEVEL BELOW THERAPEUTIC	18
23	SHORTNESS OF BREATH	18
24	NOSEBLEED	18
25	BRAIN BLEED	16

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WARFARIN SODIUM Total Medwatch Safety Reports by Patient Sex

Male	Female	Unknown	Total
539	155	39	733

Medwatch Reporter Type	Count
Consumer	59
Physician	21
Pharmacist	400
Other Health Professional	162

Top Indications

Product used for unknown indication
Atrial fibrillation
Anticoagulant therapy
Deep vein thrombosis
Budd-Chiari syndrome

Type of Outcome Reported
Serious: 540
Not Serious: 193
Note: A serious outcome means the adverse event resulted in death, a life threatening condition, hospitalization, disability, congenital anomaly, or other serious condition.

Suspected Role
Primary Suspect: 732
Concomitant Drugs: 231
Note: A single MedWatch report can list more than one drug. This summary includes WARFARIN SODIUM identified as the suspect drug or as a concomitantly taken drug.

FDA Safety-Related Labeling Changes

COUMADIN (WARFARIN SODIUM) Rx Drug:
FDA Safety-related Labeling Changes

Have experience (good or bad) with COUMADIN? Rate COUMADIN at Ask a Patient.

For serious adverse events, report them to the FDA by contacting the drug manufacturer or report directly through the MedWatch voluntary reporting form.

NOTES

This report, created by AskaPatient.com, is derived from U.S. drug-related adverse event cases that were reported directly to the FDA using the voluntary MedWatch online or paper reporting system. MedWatch is the voluntary FDA system for consumers, physicians, and others to directly report adverse reactions. The Medwatch initiative was launched in 1993 as a voluntary reporting program for consumers, physicians and other healthcare practitioners.

After processing the received forms, the FDA adds the MedWatch reports to the FDA Adverse Events Reporting System(or FAERS database.) Click here for the complete FAERS report summary, which includes mandatory reports submitted by pharmaceutical companies (worldwide) combined with the MedWatch reports. MedWatch Reports only represent about 5% of the FAERS database. For more, read "Does the FDA's Rapidly Growing Database of Adverse Events Improve Drug Safety?"

The data in this report was obtained from Open FDA. Data was last updated to include reports through January 27, 2026. The reactions, side effects, or "adverse events," represent up to the 20 most frequently occuring events in the database for a drug related to the event.

Open FDA states that it only includes the most recent version of a case report. It also adds the disclaimer: "Do not rely on Open FDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated."

FDA uses the "MedDRA" classification system to describe reported adverse reactions. MedDRA is a standardized medical terminology that facilitates sharing of regulatory information internationally. In some cases, "patient friendly" terms for the layman designated by MedDRA have been substituted for medical jargon. Please contact us with questions about this report.