Reported Reactions

Drugs

Product name as reported

Fluorouracile: adverse event reports filed with FDA

967 reports list it as a suspect or interacting product, 2010–2021.

967
reports as suspect product
0% of all reports · about 60 a year
0
reports, 12 months to June 2026
0 in the 12 months before
100%
marked serious by the reporter
57.4% across all reports
11.9%
record death among outcomes, as reported
115 reports · not verified by FDA

Between April 2010 and September 2021, 967 adverse event reports received by FDA list the product name "Fluorouracile" as reporters wrote it as a suspect or interacting product. Reports that mention it only as a concomitant medication (142) are left out of every figure here.

In the 12 months to June 2026, 0 reports listed it, and none in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 60 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are diarrhoea (7.5%), interstitial lung disease (4%) and pyrexia (3.9%). A report can list several reactions, so shares add to more than 100%; 276 different terms appear across these reports. Diarrhoea is recorded in 7.5% of these reports, against 3.1% of all reports in the database.

100% of the reports are marked serious by the reporter; 11.9% record death among the outcomes and 62.6% record hospitalisation, as reported. 39.2% of the reports came from physicians, and the largest patient age group is 45 to 64 (38.5%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

01020Jul 2021: 20Aug 2021: 20Sep 2021: 11Oct 2021: 0Nov 2021: 0Dec 2021: 02022Jan 2022: 0Feb 2022: 0Mar 2022: 0Apr 2022: 0May 2022: 0Jun 2022: 0Jul 2022: 0Aug 2022: 0Sep 2022: 0Oct 2022: 0Nov 2022: 0Dec 2022: 02023Jan 2023: 0Feb 2023: 0Mar 2023: 0Apr 2023: 0May 2023: 0Jun 2023: 0Jul 2023: 0Aug 2023: 0Sep 2023: 0Oct 2023: 0Nov 2023: 0Dec 2023: 02024Jan 2024: 0Feb 2024: 0Mar 2024: 0Apr 2024: 0May 2024: 0Jun 2024: 0Jul 2024: 0Aug 2024: 0Sep 2024: 0Oct 2024: 0Nov 2024: 0Dec 2024: 02025Jan 2025: 0Feb 2025: 0Mar 2025: 0Apr 2025: 0May 2025: 0Jun 2025: 0Jul 2025: 0Aug 2025: 0Sep 2025: 0Oct 2025: 0Nov 2025: 0Dec 2025: 02026Jan 2026: 0Feb 2026: 0Mar 2026: 0Apr 2026: 0May 2026: 0Jun 2026: 0

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

01132262010: 620102012: 182013: 5020132014: 382015: 3820152016: 252017: 3320172018: 2262019: 20520192020: 2102021: 1182021

Reactions recorded in the reports

share of Fluorouracile reports recording the termall reports in the database

  1. Diarrhoealoose or frequent stools7.5%73
  2. Interstitial lung diseasescarring or inflammation of lung tissue4%39
  3. Pyrexiafever3.9%38
  4. Thrombocytopenialow platelets3.9%38
  5. Acute kidney injurysudden loss of kidney function3.5%34
  6. Neutropenialow neutrophils, a type of white blood cell3.2%31
  7. Vomitingbeing sick3.2%31
  8. Anaemialow red blood cells3%29
  9. Astheniaweakness or lack of energy2.9%28
  10. Nauseafeeling sick2.9%28
  11. Septic shockshock arising from infection2.6%25
  12. Hyponatraemialow blood sodium2.5%24
  13. Malaisegeneral feeling of being unwell2.4%23
  14. Neuropathy peripheralnerve damage in hands or feet2.4%23
  15. Seizurea fit or convulsion2.4%23
  16. Hypokalaemialow blood potassium2.3%22
  17. Paraesthesiatingling or pins and needles2.3%22
  18. Confusional stateconfusion2.2%21
  19. Abdominal painstomach or belly pain2.1%20
  20. Dyspnoeashortness of breath2.1%20
  21. Cardiac failureheart failure2%19
  22. Chillschills or shivering2%19
  23. Dehydrationdehydration1.8%17
  24. General physical health deteriorationgeneral decline in health1.8%17
  25. Pancytopenialow counts of all blood cells1.8%17
  26. Weight decreasedweight loss1.8%17

Top 30 of 276 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the share of all reports in the database; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death11.9%115
Life-threatening11.1%107
Hospitalisation (initial or prolonged)62.6%605
Disability2.1%20
Congenital anomaly0.6%6
Other serious34.2%331
Not serious0%0

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20.6%6
2 to 110%0
12 to 170.2%2
18 to 444.4%43
45 to 6438.5%372
65 to 7431.1%301
75 and over17.5%169
Age not given7.7%74

Patient sex

Female44.5%430
Male51.1%494
Not given4.4%43

Who reported

Physician39.2%379
Pharmacist26.2%253
Other health professional27.5%266
Lawyer0%0
Consumer or non-health professional6.3%61
Not given0.8%8

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 0.1% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Adenocarcinoma of colon11712.1%
Breast cancer959.8%
Colon cancer676.9%
Colorectal cancer454.7%
Rectal cancer333.4%
Neoplasm malignant262.7%

The indication field is filled in by the reporter and is often blank; shares are of all 967 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Fluorouracile reports
Oxaliplatin31532.6%
Irinotecan20421.1%
Oxaliplatine18018.6%
Avastin13013.4%
Erbitux858.8%
Cyclophosphamide747.7%
Vectibix707.2%
Ondansetron646.6%
Emend626.4%
Methylprednisolone525.4%

Other products listed in reports where Fluorouracile is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureFluorouracileAll reports
Reports as suspect product96720,646,523
Share of that pool—0%
Reports, latest 12 months01,332,454
Marked serious100%57.4%
Death recorded among outcomes, per 1,000 reports11991
Hospitalisation recorded, per 1,000 reports626213
Consumer-filed share6.3%45.8%
Top term, share of reportsDiarrhoea 7.5%3.1%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Questions about Fluorouracile reports

How many adverse event reports has FDA received for Fluorouracile?

967 reports list Fluorouracile as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 0 of them arrived in the latest 12 months. Another 142 list it only as a concomitant medication.

What reactions are recorded in Fluorouracile reports?

diarrhoea (7.5%), interstitial lung disease (4%), pyrexia (3.9%), thrombocytopenia (3.9%) and acute kidney injury (3.5%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Fluorouracile was responsible.

How serious are the reports?

100% are marked serious by the reporter. Among the outcomes recorded, 11.9% of reports include death and 62.6% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

physician (39.2%), other health professional (27.5%) and pharmacist (26.2%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Fluorouracile rising?

0 reports in the 12 months to June 2026, and none in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Fluorouracile was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Fluorouracile?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Fluorouracile as a suspect or interacting product; reports listing it only as a concomitant medication (142) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.