Vidaza (azacitidine) adverse event reports that FDA received

Name: Reaction terms in FDA adverse event reports that name Vidaza
Creator: Reported Reactions
License: https://creativecommons.org/publicdomain/zero/1.0/

Name type: Brand name
Generic name: Azacitidine
Class: Nucleoside metabolic inhibitor

What a report is

A report is not proof that the drug was the cause of the event.

FDA says:

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.
Source: openFDA, Drug Adverse Event Overview, section "Responsible use of the data". The site read the page on 2 Oct 2026. The data have the reports that FDA received through 30 Jun 2026.

FDA also says:

There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event. The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.
Source: openFDA, Response of the drug event API (meta.disclaimer). The site read the page on 2 Oct 2026.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

Reports on file

From August 2004 to June 2026, FDA received 9,087 adverse event reports that name Vidaza. In these reports the drug is a suspect or interacting product.

In the same period, 1,670 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 358 reports in the 12 months to June 2026 and 291 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

The number of people who use the product is not in the data. A count is not a rate. A count of reports is not a count of events or of patients, because one event can have more than one report.

There are many instances of duplicative reports and some reports do not contain all the necessary information.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

Suspect product

FDA records each drug in a report as suspect, concomitant or interacting. This page counts the reports in which Vidaza is suspect or interacting. FDA says:

Any number of the drugs may be marked as suspect if thought to be responsible for one or more of the reactions, but that information is not validated.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Data version

openFDA FAERS release of 1 Oct 2026. Reports received through 30 Jun 2026.

Since the last update

FDA says:

Many factors can influence whether or not an event will be reported, such as the time a product has been marketed and publicity about an event.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

The information in these reports cannot be used to estimate the incidence (occurrence rates) of the events reported.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

No update is on record for this page. The record starts when FDA adds the reports of July to September 2026.

In April to June 2026, FDA received 78 reports that name Vidaza.
In January to March 2026, FDA received 98.
In April to June 2025, FDA received 76.

April to June 2026 is the latest closed quarter in the data. A closed quarter is a quarter for which the FDA files have most of the reports.

All updates Feed of updates (RSS)

Reaction lookup

These are the reaction terms that the reports record, with the number of reports for each term. Type a term or a plain word to find its count.

What this list leaves out

The table lists the 466 reaction terms that 5 or more reports record. A term with fewer than 5 reports is not in the table.

The site keeps reaction terms for all 9,087 reports.

The site keeps a term for a year only if two or more reports of that year record it.

So a count in the table can be lower than the count of FDA.

Find a reaction term

The table shows the first 50 of 466 terms.

Reaction terms in the reports that name Vidaza, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 9,087 reports
Deaththe patient died; cause not stated by this term	1,186	13.1%
Febrile neutropeniafever with low white blood cells	899	9.9%
Pneumonialung infection	847	9.3%
Acute myeloid leukaemia	770	8.5%
Sepsisa severe body-wide response to infection	559	6.2%
Pyrexiafever	553	6.1%
Platelet count decreasedlow platelet count	504	5.5%
Thrombocytopenialow platelets	483	5.3%
Anaemialow red blood cells	477	5.2%
Neutropenialow neutrophils, a type of white blood cell	476	5.2%
Infectionan infection, type not specified	368	4%
White blood cell count decreasedlow white cell count	365	4%
Myelodysplastic syndrome	362	4%
Pancytopenialow counts of all blood cells	338	3.7%
Nauseafeeling sick	334	3.7%
Diarrhoealoose or frequent stools	312	3.4%
Neutrophil count decreased	309	3.4%
Constipation	275	3%
Fatiguetiredness	272	3%
Vomitingbeing sick	227	2.5%
Haemoglobin decreasedlow haemoglobin	210	2.3%
Septic shockshock arising from infection	209	2.3%
Astheniaweakness or lack of energy	208	2.3%
Disease progressionthe disease advanced	208	2.3%
Rashskin rash	174	1.9%
Off label useused for a purpose or in a way not on the label	169	1.9%
Dyspnoeashortness of breath	167	1.8%
Cardiac failureheart failure	164	1.8%
Decreased appetitereduced appetite	162	1.8%
General physical health deteriorationgeneral decline in health	145	1.6%
Drug ineffectivethe medicine did not work as expected	130	1.4%
Respiratory failurethe lungs could not supply enough oxygen	129	1.4%
Interstitial lung diseasescarring or inflammation of lung tissue	119	1.3%
Renal failurekidney failure	117	1.3%
Acute myeloid leukaemia recurrent	114	1.3%
Bone marrow failure	114	1.3%
Cerebral haemorrhage	112	1.2%
No therapeutic response	112	1.2%
Pleural effusionfluid around the lung	107	1.2%
Myelodysplastic syndrome transformation	106	1.2%
Haemorrhagebleeding	105	1.2%
Cellulitisa skin infection	104	1.1%
Falla fall	103	1.1%
Urinary tract infectionbladder or urinary infection	103	1.1%
Blast cell count increased	100	1.1%
Hypotensionlow blood pressure	99	1.1%
Cytopenia	97	1.1%
Myelosuppression	97	1.1%
Abdominal painstomach or belly pain	94	1%
Leukopenialow white blood cells	94	1%

Download all 466 terms of Vidaza (CSV)

The counts add to more than 9,087 reports, because one report can record more than one term. FDA says:

No individual drug is connected to any individual reaction. When a report lists multiple drugs and multiple reactions, there is no way to conclude from the data therein that a given drug is responsible for a given reaction.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

The CSV file has the same rows and the same limits. Its last row is a note that says so.

MedDRA term

The person who codes a report selects the preferred term that agrees best with the description of the reporter. The words under a term are the plain meaning that this site gives.

Not the label

The FDA-approved label of a product lists its adverse reactions. See the official pages at the end of this page.

Same ingredient, other names

Reporters write a brand name or a generic name. Each name has its own page and its own count.

Names of Azacitidine with a page, in the order generic names, brand names, names as reported
Name	Name type	Reports
Azacitidine	Generic name	14,969
Onureg	Brand name	755
Vidaza (this page)	Brand name	9,087

Sum of the separately reported names: 24,811. A report that names two of these names is in the sum two times. The sum is not the number of reports for the ingredient.

FDA says:

Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

Outcomes by year

The table gives the outcomes that the reporters gave, in the terms of FDA.

Outcomes in the reports that name Vidaza, by the year of the openFDA file that holds the report

The table continues to the right.

Year of the openFDA file	Reports	Serious	Death	Life-threatening	Hospitalization (initial or prolonged)	Disability or Permanent Damage	Congenital Anomaly/Birth Defect	Other Serious (Important Medical Events)	Not serious
2004	18	18	9	1	14	0	0	3	0
2005	48	48	22	1	29	0	0	9	0
2006	33	33	17	1	26	0	0	6	0
2007	26	26	11	0	20	2	0	3	0
2008	84	82	23	7	59	3	0	12	2
2009	319	315	160	14	145	12	0	133	4
2010	479	476	255	21	183	18	0	214	3
2011	613	612	334	69	235	19	0	264	1
2012	744	741	425	111	356	14	0	314	3
2013	800	800	447	104	313	23	0	335	0
2014	894	889	477	134	351	19	0	381	5
2015	570	552	281	86	231	16	0	240	18
2016	479	469	236	50	203	4	0	184	10
2017	457	445	193	45	156	11	0	204	12
2018	489	469	201	28	222	7	0	158	20
2019	695	672	247	42	370	5	1	226	23
2020	489	453	165	28	238	5	0	174	36
2021	395	363	157	16	151	5	0	148	32
2022	359	337	137	23	122	6	0	251	22
2023	265	231	76	19	76	3	1	196	34
2024	285	262	87	32	113	2	1	207	23
2025	298	280	92	22	111	3	0	230	18
2026	248	232	108	12	84	3	0	181	16

An outcome in a report is not proof that the drug was the cause. The reporter gives the outcome, and FDA does not verify it. FDA says:

The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

The six headings with the names of FDA are the outcome terms of FDA. A report can have more than one outcome. The columns Serious and Not serious are the two values of the openFDA field serious. For the value serious, openFDA gives this description:

The adverse event resulted in death, a life threatening condition, hospitalization, disability, congenital anomaly, or other serious condition
Source: openFDA, Drug adverse event fields (YAML reference). The site read the page on 2 Oct 2026.

The year is the year of the openFDA file that holds the latest version of the report. It is not always the year in which FDA first received the report. The chart of the next section uses the year of first receipt. The latest year is not complete.

Reports by year and month

Reports that name Vidaza, by the year in which FDA received them

The column of 2026 has an outline, because the year is not complete. It has the reports that FDA received through June 2026 only.

Show the figures of the chart as a table

Reports that name Vidaza, by the year in which FDA received them
Year	Reports
2004	17
2005	48
2006	33
2007	26
2008	72
2009	317
2010	468
2011	645
2012	947
2013	817
2014	797
2015	572
2016	493
2017	440
2018	534
2019	640
2020	443
2021	380
2022	379
2023	245
2024	292
2025	306
2026	176

Reports that name Vidaza, by month, five years to June 2026

FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Why a count moves

A count moves for many reasons. The guide gives FDA's words about them.

Patients and reporters

Age of the patient in the reports that name Vidaza
Age	Reports	Share
Under 2	11	0.1%
2 to 11	32	0.4%
12 to 17	23	0.3%
18 to 44	223	2.5%
45 to 64	1,203	13.2%
65 to 74	2,187	24.1%
75 and over	2,438	26.8%
Age not given	2,970	32.7%

Sex of the patient in the reports that name Vidaza
Sex	Reports	Share
Female	2,939	32.3%
Male	4,890	53.8%
Unknown or not given	1,258	13.8%

Type of reporter in the reports that name Vidaza
Reporter	Reports	Share
Physician	4,168	45.9%
Pharmacist	429	4.7%
Other health professional	3,298	36.3%
Lawyer	0	0%
Consumer or non-health professional	873	9.6%
Not given	319	3.5%

Age and sex are as the report gives them. The reporter is the primary source in the report. 24.9% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Vidaza record
Indication as recorded (MedDRA)	Reports	Share
Myelodysplastic syndrome	3,097	34.1%
Acute myeloid leukaemia	2,033	22.4%
Chronic myelomonocytic leukaemia	191	2.1%
Mds	100	1.1%
Refractory anaemia with an excess of blasts	64	0.7%
Acute leukaemia	43	0.5%

The reporter fills in the indication, and the field is often empty. Each share is of all 9,087 reports.

Drugs in the same reports

Other drugs that the reports of Vidaza name, in any role, in order of name
Drug	Reports that name the two
Acyclovir	258
Allopurinol	425
Cytarabine	259
Exjade	223
Fluconazole	324
Furosemide	223
Ondansetron	321
Revlimid	370
Venclexta	538
Venetoclax	629

The table has the 10 drug names that these reports name most. Two names in one report says only that the report recorded the two. It says nothing about the part of a product in the event.

FDA says:

Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

Pages near this one

Azacitidine same ingredient
Onureg same ingredient
Purixan same class
Xeloda same class
Pentostatin same class
Victrelis next in the A to Z list
Videx next in the A to Z list
Victoza Solution for Injection 6mg/Ml next in the A to Z list
Videx Ec next in the A to Z list
Victoza Solution for Injection 6 Mg/Ml next in the A to Z list
Viekira Pak next in the A to Z list
Victoza next in the A to Z list

These links are for navigation. No count selected them. The class page lists each drug of the class.

Official pages

DailyMed labels for VidazaThe labels (prescribing information) that have this name, at the National Library of Medicine.
MedWatch Online Voluntary Reporting FormThe online form of FDA for a voluntary report.
MedWatch: The FDA Safety Information and Adverse Event Reporting ProgramThe page of the FDA program that receives reports about drugs and devices.
FDA Adverse Event Monitoring System (AEMS) Public DashboardThe public dashboard of FDA for adverse event reports on drugs and biologics.

The site checked these addresses on 2 Oct 2026. The links open in a new tab.

Cite this page

Reported Reactions. Vidaza: adverse event reports that FDA received. https://reportedreactions.com/drug/vidaza/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of 1 Oct 2026. Reports received through 30 Jun 2026.

Where the data come from

The counts come from the openFDA Drug Adverse Event (FAERS) bulk files, release of 1 Oct 2026. The files have the reports that FDA received through 30 Jun 2026. A drug name is the name on the report. The site matches it to a brand name or a generic name of the National Drug Code Directory of 2 Oct 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Vidaza as a suspect or interacting product. The 1,670 reports that name it only as a concomitant medicine are not in the count. The site does not publish a report narrative, a lot number, a detail of a patient or the identity of a reporter. The record of FDA is the authority. See how the site counts reports, the data sources and the corrections page.

Questions

Do these reports show that Vidaza was responsible for the reactions?

No. FDA says:

For any given report, there is no certainty that a suspected drug caused the event.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

A reaction can relate to the condition that the drug treats, to other medicines, or to something else.

Is this the list of reactions on the label of Vidaza?

No. It is a count of what people reported to FDA: 9,087 reports from August 2004 to June 2026. The FDA-approved label of a product lists its adverse reactions. The official pages at the end of this page link to the labels.

Who sent these reports?

Physician (45.9%), other health professional (36.3%) and consumer or non-health professional (9.6%). These are the types of reporter for the reports that name this drug.

If a manufacturer receives an adverse event report, it is normally required to send the report to FDA.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

How does a person report an adverse event?

FDA runs MedWatch, a program that takes voluntary reports from health professionals, patients and consumers. The guide on how to report has the links.

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