Reported Reactions

Drugs › Nucleoside metabolic inhibitor

Generic name

Decitabine: adverse event reports filed with FDA

3,026 reports list it as a suspect or interacting product, 2005–2026. Class: Nucleoside metabolic inhibitor. Also reported as Inj Decitabine, Decitabine Injection.

3,026
reports as suspect product
0% of all reports · about 144 a year
258
reports, 12 months to June 2026
261 in the 12 months before
96.8%
marked serious by the reporter
92.2% across the class
25.1%
record death among outcomes, as reported
760 reports · not verified by FDA

Between July 2005 and June 2026, 3,026 adverse event reports received by FDA list decitabine, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (1,287) are left out of every figure here.

In the 12 months to June 2026, 258 reports listed it, close to the 261 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 144 reports a year and 0% of the 20,646,523 reports in the database, and 1% of the reports for the nucleoside metabolic inhibitor class. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are febrile neutropenia (12.1%), myelosuppression (11%) and off label use (8.8%). A report can list several reactions, so shares add to more than 100%; 553 different terms appear across these reports. Febrile neutropenia is recorded in 12.1% of these reports, a larger share than in the median nucleoside metabolic inhibitor drug (5%).

96.8% of the reports are marked serious by the reporter (92.2% across the class); 25.1% record death among the outcomes and 36.2% record hospitalisation, as reported. 55.3% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (22.9%). 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

03977Jul 2021: 26Aug 2021: 18Sep 2021: 27Oct 2021: 29Nov 2021: 21Dec 2021: 262022Jan 2022: 30Feb 2022: 28Mar 2022: 26Apr 2022: 24May 2022: 28Jun 2022: 77Jul 2022: 30Aug 2022: 13Sep 2022: 37Oct 2022: 39Nov 2022: 9Dec 2022: 372023Jan 2023: 27Feb 2023: 17Mar 2023: 11Apr 2023: 47May 2023: 28Jun 2023: 26Jul 2023: 39Aug 2023: 27Sep 2023: 15Oct 2023: 23Nov 2023: 22Dec 2023: 322024Jan 2024: 23Feb 2024: 18Mar 2024: 24Apr 2024: 21May 2024: 22Jun 2024: 29Jul 2024: 16Aug 2024: 37Sep 2024: 43Oct 2024: 22Nov 2024: 10Dec 2024: 242025Jan 2025: 12Feb 2025: 8Mar 2025: 21Apr 2025: 33May 2025: 25Jun 2025: 10Jul 2025: 25Aug 2025: 22Sep 2025: 14Oct 2025: 18Nov 2025: 17Dec 2025: 182026Jan 2026: 69Feb 2026: 9Mar 2026: 20Apr 2026: 12May 2026: 13Jun 2026: 21

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

01893782005: 320052007: 82008: 132009: 4820092010: 192011: 952012: 11520122013: 692014: 622015: 5720152016: 772017: 1332018: 17620182019: 2012020: 3292021: 27320212022: 3782023: 3142024: 28920242025: 2232026: 144

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Decitabine reports recording the termmedian drug in nucleoside metabolic inhibitor

  1. Febrile neutropeniafever with low white blood cells12.1%365
  2. Off label useused for a purpose or in a way not on the label8.8%267
  3. Pneumonialung infection8.4%253
  4. Drug ineffectivethe medicine did not work as expected8.1%244
  5. Neutropenialow neutrophils, a type of white blood cell6.3%190
  6. Product use in unapproved indicationused for a purpose not on the label6%181
  7. Thrombocytopenialow platelets5.7%173
  8. Sepsisa severe body-wide response to infection5.6%168
  9. Pyrexiafever5.3%159
  10. Disease progressionthe disease advanced5.1%155
  11. Infectionan infection, type not specified4.5%135
  12. Nauseafeeling sick4%122
  13. Anaemialow red blood cells3.7%111
  14. Deaththe patient died; cause not stated by this term3%91
  15. Pancytopenialow counts of all blood cells2.9%88
  16. Respiratory failurethe lungs could not supply enough oxygen2.9%87
  17. Diarrhoealoose or frequent stools2.8%84
  18. Therapy non-responderthe treatment did not work2.7%83
  19. Fatiguetiredness2.5%76
  20. Dyspnoeashortness of breath2.4%74
  21. Platelet count decreasedlow platelet count2.3%69
  22. Septic shockshock arising from infection2.2%66
  23. Cardiac failureheart failure1.9%59
  24. Vomitingbeing sick1.9%59
  25. White blood cell count decreasedlow white cell count1.9%59
  26. Astheniaweakness or lack of energy1.8%55

Top 30 of 553 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 median share across the 19 drugs in the nucleoside metabolic inhibitor class; 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

Death25.1%760
Life-threatening7.1%214
Hospitalisation (initial or prolonged)36.2%1,096
Disability0.4%11
Congenital anomaly0%1
Other serious66.5%2,011
Not serious3.2%97

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 313,386 reports in the class. 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 21.2%35
2 to 114.4%133
12 to 173%91
18 to 449.8%298
45 to 6422.9%694
65 to 7420.5%620
75 and over13.5%407
Age not given24.7%748

Patient sex

Female34.5%1,044
Male46.3%1,402
Not given19.2%580

Who reported

Physician34.6%1,046
Pharmacist1.7%50
Other health professional55.3%1,672
Lawyer0%0
Consumer or non-health professional6.9%208
Not given1.7%50

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 55.9% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Acute myeloid leukaemia1,30343.1%
Myelodysplastic syndrome39513.1%
Chemotherapy722.4%
Acute myeloid leukaemia refractory602%
Chronic myelomonocytic leukaemia561.9%
Acute lymphocytic leukaemia401.3%

The indication field is filled in by the reporter and is often blank; shares are of all 3,026 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Decitabine reports
Venetoclax98132.4%
Cytarabine64421.3%
Cyclophosphamide2428%
Azacitidine2177.2%
Fludarabine2016.6%
Methotrexate1685.6%
Busulfan1525%
Acyclovir1324.4%
Etoposide1304.3%
Dexamethasone1153.8%

Other products listed in reports where Decitabine 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

MeasureDecitabineNucleoside metabolic inhibitorAll reports
Reports as suspect product3,026313,38620,646,523
Share of that pool—1%0%
Reports, latest 12 months258—1,332,454
Marked serious96.8%92.2%57.4%
Death recorded among outcomes, per 1,000 reports25121091
Hospitalisation recorded, per 1,000 reports362380213
Consumer-filed share6.9%11.4%45.8%
Top term, share of reportsFebrile neutropenia 12.1%median 5%0.3%

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."

Other drugs in the nucleoside metabolic inhibitor class

DrugName typeReportsLatest 12 monthsMarked serious
Fluorouracilgeneric60,4515,31596.1%
Capecitabinegeneric51,7833,28183.3%
Cytarabinegeneric50,7413,54597.9%
Gemcitabinegeneric33,1982,92097.9%
Xelodabrand32,27928073%
Fludarabinebrand20,2601,90098.7%
Azacitidinegeneric14,9691,83098%
Gemcitabine hydrochloridegeneric12,3991,16497.1%
Mercaptopurinegeneric10,54050795.8%
Vidazabrand9,08735896.9%
Fludarabine phosphategeneric8,42641998.5%
Clofarabinegeneric2,0207796.5%
Purixangeneric7672981.5%
Onuregbrand7556949.8%
Pentostatingeneric6971691.7%

Ordered by report count for navigation only. 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." A brand and its generic are separate rows because reporters name them separately.

Questions about Decitabine reports

How many adverse event reports has FDA received for Decitabine?

3,026 reports list Decitabine as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 258 of them arrived in the latest 12 months. Another 1,287 list it only as a concomitant medication.

What reactions are recorded in Decitabine reports?

febrile neutropenia (12.1%), myelosuppression (11%), off label use (8.8%), pneumonia (8.4%) and drug ineffective (8.1%). 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 Decitabine was responsible.

How serious are the reports?

96.8% are marked serious by the reporter. Among the outcomes recorded, 25.1% of reports include death and 36.2% 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 (55.3%), physician (34.6%) and consumer or non-health professional (6.9%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Decitabine rising?

258 reports in the 12 months to June 2026, close to the 261 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 Decitabine 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 Decitabine?

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 Decitabine as a suspect or interacting product; reports listing it only as a concomitant medication (1,287) 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.