Reported Reactions

Adverse event reports that FDA received

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Alkylating drug adverse event reports that FDA received for the drugs of this class

Kind of class
Pharmacologic class (FDA Established Pharmacologic Class)
Drug pages
23

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 . The data have the reports that FDA received through .

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 .

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 .

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

Alkylating drug is a pharmacologic class: an FDA Established Pharmacologic Class. The class has 23 drug pages on this site.

From January 2004 to June 2026, FDA received 253,205 adverse event reports that name a drug of the class. In these reports the drug is a suspect or interacting product. A report that names two drugs of the class counts one time for each.

FDA received 19,663 reports in the 12 months to June 2026 and 21,675 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, 19,663 (1.5%) name a drug of the class. Reports from consumers or other non-health professionals were 6.3% of the reports that name a drug of the class 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.

Pharmacologic class

The Established Pharmacologic Class (EPC) of FDA is the class on the label of a drug. The site puts a drug in the class that its reports have most often.

Data version

openFDA FAERS release of 29 Oct 2026. Reports received through 30 Jun 2026.

Drugs of the class

The rows are in order of name. A brand name and its generic name are separate rows, because reporters name them separately.

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 .

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 . The site read the page on .

Drug pages of the class Alkylating drug, in order of name
DrugName typeReportsReports, 12 months to June 2026
Bendamustine hydrochlorideGeneric name6,941253
BusulfanGeneric name11,8251,095
CarmustineGeneric name3,378180
ChlorambucilGeneric name2,48675
CyclophosphamideGeneric name141,09912,360
DacarbazineGeneric name6,431511
GleostineLomustineBrand name51526
GliadelCarmustineBrand name5232
IfexIfosfamideBrand name54311
IfosfamideGeneric name18,6581,325
LomustineGeneric name1,10092
MatulaneProcarbazine hydrochlorideBrand name3,845284
MelphalanGeneric name17,190956
MitomycinGeneric name2,041117
Procarbazine hydrochlorideGeneric name55730
TemodarTemozolomideBrand name4,65224
TemozolomideGeneric name15,3241,055
ThiotepaGeneric name7,8531,035
TrabectedinGeneric name1,09999
TreandaBendamustine hydrochlorideBrand name3,3303
ValchlorMechlorethamine hydrochlorideBrand name2,11416
YondelisTrabectedinBrand name1,09957
ZepzelcaLurbinectedinBrand name60257

Reaction lookup

These are the reaction terms that the reports of the class record. Type a term or a plain word to find its count.

What this list leaves out

The table lists the 4,403 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 252,306 of the 253,205 reports (99.6%).

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.

The table shows the first 50 of 4,403 terms.

Reaction terms in the reports that name a alkylating drug drug, most reports first
Reaction term (MedDRA) and plain meaningReportsShare of the 253,205 reports
Off label useused for a purpose or in a way not on the label23,8209.4%
Febrile neutropeniafever with low white blood cells20,5358.1%
Neutropenialow neutrophils, a type of white blood cell14,9425.9%
Drug ineffectivethe medicine did not work as expected14,0575.6%
Disease progressionthe disease advanced13,7355.4%
Pyrexiafever11,8794.7%
Thrombocytopenialow platelets11,2894.5%
Product use in unapproved indicationused for a purpose not on the label11,2304.4%
Nauseafeeling sick9,6463.8%
Anaemialow red blood cells8,8853.5%
Pneumonialung infection8,6263.4%
Sepsisa severe body-wide response to infection8,2103.2%
Deaththe patient died; cause not stated by this term7,7873.1%
Diarrhoealoose or frequent stools7,6483%
Vomitingbeing sick7,2782.9%
Infectionan infection, type not specified7,0212.8%
Mucosal inflammation6,8662.7%
Pancytopenialow counts of all blood cells6,7442.7%
Fatiguetiredness6,1972.4%
Myelosuppression5,4452.2%
Malignant neoplasm progression5,2392.1%
White blood cell count decreasedlow white cell count4,8011.9%
Dyspnoeashortness of breath4,2691.7%
Platelet count decreasedlow platelet count4,2271.7%
Neuropathy peripheralnerve damage in hands or feet4,1851.7%
Leukopenialow white blood cells4,1381.6%
Septic shockshock arising from infection4,0281.6%
Myelodysplastic syndrome4,0021.6%
Respiratory failurethe lungs could not supply enough oxygen3,9741.6%
Astheniaweakness or lack of energy3,9571.6%
Acute myeloid leukaemia3,8651.5%
Acute kidney injurysudden loss of kidney function3,7911.5%
Cytomegalovirus infection3,7901.5%
Neutrophil count decreased3,3561.3%
Toxicity to various agentspoisoning or toxic effect of one or more substances3,2471.3%
Hypotensionlow blood pressure3,1071.2%
Condition aggravatedthe condition being treated got worse3,0241.2%
Covid-19COVID-19 infection2,9841.2%
Cytokine release syndrome2,9611.2%
Bone marrow failure2,9211.2%
Rashskin rash2,9141.2%
Headachehead pain2,9071.1%
Decreased appetitereduced appetite2,8771.1%
Venoocclusive liver disease2,8721.1%
Plasma cell myeloma2,8631.1%
Abdominal painstomach or belly pain2,8331.1%
Multiple organ dysfunction syndromeseveral organs failing2,7501.1%
Product use issuea problem in how the product was used2,6981.1%
Haematotoxicity2,6921.1%
Renal failurekidney failure2,6641.1%

Download all 4,403 terms of the class (CSV)

The counts add to more than 253,205 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 .

Reports by month

Reports that name a alkylating drug drug, by month, five years to June 2026
02,5005,00020222023202420252026

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

Outcomes, patients and reporters

Outcomes in the reports of the class Alkylating drug
OutcomeReportsShareShare as a bar
Death52,61520.8%
Life-threatening18,8697.5%
Hospitalization (initial or prolonged)84,33233.3%
Disability or Permanent Damage3,1991.3%
Congenital Anomaly/Birth Defect5900.2%
Other Serious (Important Medical Events)162,94264.4%
Not serious16,4656.5%

An outcome in a report is not proof that a drug was the cause. The reporter gives the outcome, and FDA does not verify it. A report can have more than one outcome. 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 .

Age of the patient in the reports of the class Alkylating drug
AgeReportsShareShare as a bar
Under 24,2971.7%
2 to 1116,0776.3%
12 to 179,7963.9%
18 to 4434,34613.6%
45 to 6458,66023.2%
65 to 7431,86512.6%
75 and over15,6516.2%
Age not given82,51332.6%
Type of reporter in the reports of the class Alkylating drug
ReporterReportsShareShare as a bar
Physician104,47441.3%
Pharmacist9,3963.7%
Other health professional110,67843.7%
Lawyer1800.1%
Consumer or non-health professional15,8726.3%
Not given12,6055%

Official pages

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

Cite this page

Reported Reactions. Alkylating drug: adverse event reports that FDA received. https://reportedreactions.com/class/alkylating-drug/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of . Reports received through .

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.

The class of a drug is the Established Pharmacologic Class that openFDA attaches to its reports most often. When the reports have none, it is the class in the NDC Directory. 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

Which drugs are in the Alkylating drug class on this site?

Bendamustine hydrochloride, Busulfan, Carmustine, Chlorambucil, Cyclophosphamide, Dacarbazine and 17 more, in order of name. The class of a drug comes from the pharmacologic class (EPC) on its FDA label.

Can the table of drugs rank the drugs?

No. FDA says:

Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

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 .

Drugs also differ in the conditions that they treat and in their time on the market.

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.