Reported Reactions

Drugs

Generic name

Irinotecan: adverse event reports filed with FDA

20,237 reports list it as a suspect or interacting product, 2004–2026. Also reported as Irinotecan Capsule, Irinotecan Injection, Irinotecan /01280202/.

20,237
reports as suspect product
0.1% of all reports · about 900 a year
1,652
reports, 12 months to June 2026
1,512 in the 12 months before
98%
marked serious by the reporter
57.4% across all reports
15.6%
record death among outcomes, as reported
3,156 reports · not verified by FDA

Between January 2004 and June 2026, 20,237 adverse event reports received by FDA list irinotecan, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (5,725) are left out of every figure here.

In the 12 months to June 2026, 1,652 reports listed it, close to the 1,512 of 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 900 reports a year and 0.1% 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 (15.9%), neutropenia (10.4%) and disease progression (9.4%). A report can list several reactions, so shares add to more than 100%; 1,734 different terms appear across these reports. Diarrhoea is recorded in 15.9% of these reports, against 3.1% of all reports in the database.

98% of the reports are marked serious by the reporter; 15.6% record death among the outcomes and 35.8% record hospitalisation, as reported. 45.3% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (30.5%). 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

0122243Jul 2021: 112Aug 2021: 136Sep 2021: 85Oct 2021: 89Nov 2021: 96Dec 2021: 1172022Jan 2022: 109Feb 2022: 79Mar 2022: 88Apr 2022: 93May 2022: 127Jun 2022: 130Jul 2022: 115Aug 2022: 106Sep 2022: 115Oct 2022: 157Nov 2022: 187Dec 2022: 1622023Jan 2023: 120Feb 2023: 156Mar 2023: 132Apr 2023: 115May 2023: 243Jun 2023: 136Jul 2023: 159Aug 2023: 166Sep 2023: 143Oct 2023: 133Nov 2023: 101Dec 2023: 1422024Jan 2024: 115Feb 2024: 108Mar 2024: 110Apr 2024: 125May 2024: 105Jun 2024: 140Jul 2024: 128Aug 2024: 91Sep 2024: 124Oct 2024: 148Nov 2024: 120Dec 2024: 1372025Jan 2025: 154Feb 2025: 111Mar 2025: 169Apr 2025: 119May 2025: 98Jun 2025: 113Jul 2025: 203Aug 2025: 147Sep 2025: 122Oct 2025: 164Nov 2025: 119Dec 2025: 1302026Jan 2026: 109Feb 2026: 112Mar 2026: 126Apr 2026: 143May 2026: 146Jun 2026: 131

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

09961,9912004: 29520042005: 1772006: 572007: 1520072008: 632009: 142010: 4720102011: 762012: 3372013: 1,11020132014: 8642015: 1,1342016: 1,54320162017: 1,2492018: 1,9912019: 1,62520192020: 1,2922021: 1,2672022: 1,46820222023: 1,7462024: 1,4512025: 1,64920252026: 767

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Irinotecan reports recording the termall reports in the database

  1. Diarrhoealoose or frequent stools15.9%3,218
  2. Neutropenialow neutrophils, a type of white blood cell10.4%2,106
  3. Disease progressionthe disease advanced9.4%1,897
  4. Nauseafeeling sick8.5%1,716
  5. Vomitingbeing sick7.2%1,454
  6. Fatiguetiredness6%1,207
  7. Thrombocytopenialow platelets5.3%1,067
  8. Off label useused for a purpose or in a way not on the label5.2%1,059
  9. Neuropathy peripheralnerve damage in hands or feet5%1,014
  10. Anaemialow red blood cells5%1,013
  11. Drug ineffectivethe medicine did not work as expected4.9%990
  12. Febrile neutropeniafever with low white blood cells4.8%976
  13. Astheniaweakness or lack of energy4.2%851
  14. Pyrexiafever3.9%783
  15. Decreased appetitereduced appetite3.8%760
  16. Abdominal painstomach or belly pain3.5%701
  17. Hypertensionhigh blood pressure3.2%647
  18. Leukopenialow white blood cells2.9%582
  19. Deaththe patient died; cause not stated by this term2.8%567
  20. General physical health deteriorationgeneral decline in health2.7%547
  21. Dehydrationdehydration2.6%531
  22. Stomatitissore mouth2.5%515
  23. Rashskin rash2.2%454
  24. Dyspnoeashortness of breath2.1%432
  25. Pulmonary embolisma blood clot in the lung2%414
  26. Toxicity to various agentspoisoning or toxic effect of one or more substances1.9%382
  27. Alopeciahair loss1.9%377

Top 30 of 1,734 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

Death15.6%3,156
Life-threatening5.9%1,201
Hospitalisation (initial or prolonged)35.8%7,236
Disability1%195
Congenital anomaly0.1%20
Other serious68.1%13,784
Not serious2%414

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 20.4%74
2 to 112.6%534
12 to 171.5%303
18 to 447.4%1,495
45 to 6430.5%6,179
65 to 7421.5%4,358
75 and over8.3%1,679
Age not given27.7%5,615

Patient sex

Female32.5%6,573
Male44.6%9,035
Not given22.9%4,629

Who reported

Physician39.3%7,947
Pharmacist7.5%1,523
Other health professional45.3%9,163
Lawyer0%10
Consumer or non-health professional5.2%1,048
Not given2.7%546

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 20% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Colorectal cancer metastatic3,58917.7%
Colon cancer1,2346.1%
Colorectal cancer1,1015.4%
Pancreatic carcinoma1,0495.2%
Adenocarcinoma of colon8274.1%
Adenocarcinoma pancreas6493.2%

The indication field is filled in by the reporter and is often blank; shares are of all 20,237 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Irinotecan reports
Fluorouracil11,38656.3%
Oxaliplatin7,88539%
Bevacizumab4,75823.5%
Leucovorin4,30521.3%
Folinic Acid2,99114.8%
Capecitabine1,8939.4%
Leucovorin calcium1,6668.2%
Avastin1,4117%
Cetuximab1,3926.9%
Dexamethasone1,3366.6%

Other products listed in reports where Irinotecan 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

MeasureIrinotecanAll reports
Reports as suspect product20,23720,646,523
Share of that pool—0.1%
Reports, latest 12 months1,6521,332,454
Marked serious98%57.4%
Death recorded among outcomes, per 1,000 reports15691
Hospitalisation recorded, per 1,000 reports358213
Consumer-filed share5.2%45.8%
Top term, share of reportsDiarrhoea 15.9%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 Irinotecan reports

How many adverse event reports has FDA received for Irinotecan?

20,237 reports list Irinotecan as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 1,652 of them arrived in the latest 12 months. Another 5,725 list it only as a concomitant medication.

What reactions are recorded in Irinotecan reports?

diarrhoea (15.9%), neutropenia (10.4%), disease progression (9.4%), nausea (8.5%) and vomiting (7.2%). 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 Irinotecan was responsible.

How serious are the reports?

98% are marked serious by the reporter. Among the outcomes recorded, 15.6% of reports include death and 35.8% 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?

other health professional (45.3%), physician (39.3%) and pharmacist (7.5%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Irinotecan rising?

1,652 reports in the 12 months to June 2026, close to the 1,512 of 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 Irinotecan 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 Irinotecan?

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 Irinotecan as a suspect or interacting product; reports listing it only as a concomitant medication (5,725) 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.