Busulfex adverse event reports that FDA received

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

Name type: Product name as reported

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.

Drug reports received through 30 Jun 2026. Device reports have a separate cutoff, 30 Sep 2026. Why a report count is not a rate.

Reports on file

From January 2004 to June 2026, FDA received 2,573 adverse event reports that name Busulfex. The name is as reporters wrote it. In these reports the drug is a suspect or interacting product.

In the same period, 141 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 11 reports in the 12 months to June 2026 and 44 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Of the 1,332,454 drug reports that FDA received in the 12 months to June 2026, 11 (under 0.1%) name Busulfex. Reports from consumers or other non-health professionals were 4.2% of the reports that name Busulfex and 45.8% of all drug reports.

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 Busulfex 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 29 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.

The latest update of the FDA data, recorded on 28 Oct 2026, changed no count of this page.

In April to June 2026, FDA received 2 reports that name Busulfex.
In January to March 2026, FDA received 4.
In April to June 2025, FDA received 12.

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 240 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 2,553 of the 2,573 reports (99.2%).

The reports of the other years are not in the counts.

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 240 terms.

Reaction terms in the reports that name Busulfex, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 2,573 reports
Sepsisa severe body-wide response to infection	199	7.7%
Acute graft versus host disease	198	7.7%
Stomatitissore mouth	175	6.8%
Off label useused for a purpose or in a way not on the label	171	6.6%
Venoocclusive liver disease	167	6.5%
Diarrhoealoose or frequent stools	156	6.1%
Graft versus host disease	131	5.1%
Nauseafeeling sick	127	4.9%
Mucosal inflammation	126	4.9%
Anorexia	119	4.6%
Febrile neutropeniafever with low white blood cells	117	4.5%
Drug administration errora mistake in giving the medicine	116	4.5%
Chronic graft versus host disease	115	4.5%
Cytomegalovirus infection	114	4.4%
Product use in unapproved indicationused for a purpose not on the label	114	4.4%
Malaisegeneral feeling of being unwell	113	4.4%
Thrombotic microangiopathy	103	4%
Vomitingbeing sick	93	3.6%
Meningitis tuberculous	92	3.6%
Acute myeloid leukaemia recurrent	89	3.5%
Infectionan infection, type not specified	88	3.4%
Acute graft versus host disease in skin	87	3.4%
Pneumonialung infection	85	3.3%
Venoocclusive disease	81	3.1%
Pyrexiafever	72	2.8%
Bone marrow failure	62	2.4%
Respiratory failurethe lungs could not supply enough oxygen	61	2.4%
Malignant neoplasm progression	60	2.3%
Pancytopenialow counts of all blood cells	60	2.3%
Acute graft versus host disease in intestine	59	2.3%
Cystitis haemorrhagic	58	2.3%
Cytomegalovirus viraemia	55	2.1%
Stem cell transplant	53	2.1%
Disease recurrencethe disease came back	50	1.9%
Thrombocytopenialow platelets	50	1.9%
Bone marrow transplant	49	1.9%
Deaththe patient died; cause not stated by this term	49	1.9%
Multi-organ failure	46	1.8%
Skin toxicity	46	1.8%
Blood bilirubin increased	45	1.7%
Convulsion	44	1.7%
Drug intolerancethe medicine was not tolerated	44	1.7%
Lymphadenopathyswollen lymph nodes	44	1.7%
Bone marrow transplant rejection	43	1.7%
Disease progressionthe disease advanced	43	1.7%
Leukaemia recurrent	43	1.7%
No adverse eventno adverse event was reported	42	1.6%
Staphylococcal sepsis	42	1.6%
Acute myeloid leukaemia	40	1.6%
Platelet count decreasedlow platelet count	39	1.5%

Download all 240 terms of Busulfex (CSV)

The counts add to more than 2,573 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.

Outcomes by year

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

Outcomes in the reports that name Busulfex, 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	3	3	1	0	2	0	0	0	0
2005	18	18	9	2	7	0	0	0	0
2006	2	2	1	0	0	0	0	1	0
2007	5	5	3	1	2	0	0	1	0
2008	199	173	92	97	79	16	0	2	26
2009	103	60	43	13	17	4	0	9	43
2010	442	430	200	11	16	1	0	316	12
2011	107	107	59	5	16	0	0	64	0
2012	97	97	60	2	7	1	0	59	0
2013	248	243	90	17	47	2	0	156	5
2014	190	181	74	13	15	3	0	125	9
2015	78	78	33	2	8	1	0	59	0
2016	98	55	28	5	11	3	0	34	43
2017	102	80	39	5	7	2	0	56	22
2018	114	93	39	3	16	2	1	65	21
2019	172	147	63	14	31	3	0	106	25
2020	213	199	70	1	34	4	0	156	14
2021	118	115	38	8	44	1	0	89	3
2022	86	85	26	5	21	0	1	72	1
2023	72	72	20	2	11	0	0	68	0
2024	54	54	9	3	8	0	0	53	0
2025	42	42	15	4	9	1	0	40	0
2026	10	6	2	1	1	0	0	5	4

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 Busulfex, 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 Busulfex, by the year in which FDA received them
Year	Reports
2004	3
2005	18
2006	2
2007	3
2008	198
2009	104
2010	400
2011	130
2012	125
2013	262
2014	198
2015	75
2016	107
2017	104
2018	129
2019	186
2020	200
2021	111
2022	67
2023	69
2024	49
2025	27
2026	6

Reports that name Busulfex, 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 Busulfex
Age	Reports	Share
Under 2	173	6.7%
2 to 11	410	15.9%
12 to 17	156	6.1%
18 to 44	440	17.1%
45 to 64	566	22%
65 to 74	108	4.2%
75 and over	2	0.1%
Age not given	718	27.9%

Sex of the patient in the reports that name Busulfex
Sex	Reports	Share
Female	765	29.7%
Male	1,083	42.1%
Unknown or not given	725	28.2%

Type of reporter in the reports that name Busulfex
Reporter	Reports	Share
Physician	1,191	46.3%
Pharmacist	33	1.3%
Other health professional	836	32.5%
Lawyer	0	0%
Consumer or non-health professional	108	4.2%
Not given	405	15.7%

Age and sex are as the report gives them. The reporter is the primary source in the report. 24.7% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Busulfex record
Indication as recorded (MedDRA)	Reports	Share
Stem cell transplant	1,186	46.1%
Bone marrow conditioning regimen	346	13.4%
Cord blood transplant therapy	121	4.7%
Acute myeloid leukaemia	94	3.7%
Allogenic stem cell transplantation	80	3.1%
B-cell lymphoma	80	3.1%

The reporter fills in the indication, and the field is often empty. Each share is of all 2,573 reports.

Drugs in the same reports

Other drugs that the reports of Busulfex name, in any role, in order of name
Drug	Reports that name the two
Cyclophosphamide	915
Cyclosporine	448
Etoposide	284
Filgrastim	262
Fludarabine	480
Fludarabine phosphate	640
Melphalan	392
Methotrexate	569
Mycophenolate mofetil	219
Tacrolimus	325

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

Busulfan next in the A to Z list
Busulphan next in the A to Z list
Buspirone hydrochloride next in the A to Z list
Butalbital next in the A to Z list
Buspirone hcl next in the A to Z list
Butalbital Acetaminophen and Caffeine with Codeine Phosphate next in the A to Z list
Buspirone next in the A to Z list
Butalbital, acetaminophen, and caffeine next in the A to Z list
Buspar next in the A to Z list
Butorphanol tartrate next in the A to Z list
Busilvex next in the A to Z list
Butrans next in the A to Z list

These links are for navigation. No count selected them.

Official pages

DailyMed labels for BusulfexThe 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. Busulfex: adverse event reports that FDA received. https://reportedreactions.com/drug/busulfex/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of 29 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 29 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 Nov 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Busulfex as a suspect or interacting product. The 141 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 Busulfex 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 Busulfex?

No. It is a count of what people reported to FDA: 2,573 reports from January 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 (46.3%), other health professional (32.5%) and consumer or non-health professional (4.2%). 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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