Leucovorin adverse event reports that FDA received

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

Name type: Product name as reported
Also reported as: Leucovorin /00566701/, Leucovorin /00566702/

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 February 2004 to June 2026, FDA received 13,519 adverse event reports that name Leucovorin. The name is as reporters wrote it. In these reports the drug is a suspect or interacting product.

In the same period, 9,189 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 1,476 reports in the 12 months to June 2026 and 1,493 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, 1,476 (0.1%) name Leucovorin. Reports from consumers or other non-health professionals were 5.8% of the reports that name Leucovorin 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 Leucovorin 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 376 reports that name Leucovorin.
In January to March 2026, FDA received 341.
In April to June 2025, FDA received 398.

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 963 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 13,463 of the 13,519 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.

Find a reaction term

The table shows the first 50 of 963 terms.

Reaction terms in the reports that name Leucovorin, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 13,519 reports
Diarrhoealoose or frequent stools	1,581	11.7%
Neutropenialow neutrophils, a type of white blood cell	1,194	8.8%
Nauseafeeling sick	1,107	8.2%
Drug ineffectivethe medicine did not work as expected	1,040	7.7%
Off label useused for a purpose or in a way not on the label	1,010	7.5%
Disease progressionthe disease advanced	939	6.9%
Neuropathy peripheralnerve damage in hands or feet	923	6.8%
Febrile neutropeniafever with low white blood cells	907	6.7%
Vomitingbeing sick	792	5.9%
Fatiguetiredness	768	5.7%
Thrombocytopenialow platelets	658	4.9%
Pyrexiafever	635	4.7%
Anaemialow red blood cells	579	4.3%
Abdominal painstomach or belly pain	464	3.4%
Deaththe patient died; cause not stated by this term	431	3.2%
Malignant neoplasm progression	429	3.2%
Astheniaweakness or lack of energy	404	3%
Decreased appetitereduced appetite	396	2.9%
Rashskin rash	372	2.8%
Sepsisa severe body-wide response to infection	362	2.7%
Product use in unapproved indicationused for a purpose not on the label	360	2.7%
Hypertensionhigh blood pressure	343	2.5%
Stomatitissore mouth	330	2.4%
Mucosal inflammation	319	2.4%
General physical health deteriorationgeneral decline in health	317	2.3%
Dyspnoeashortness of breath	310	2.3%
Toxicity to various agentspoisoning or toxic effect of one or more substances	307	2.3%
Pulmonary embolisma blood clot in the lung	299	2.2%
Acute kidney injurysudden loss of kidney function	298	2.2%
Leukopenialow white blood cells	284	2.1%
Pneumonialung infection	284	2.1%
Neurotoxicity	279	2.1%
Dehydration	273	2%
Neoplasm progression	270	2%
Skin toxicity	264	2%
Therapy partial responder	260	1.9%
Colorectal cancer metastatic	257	1.9%
Weight decreasedweight loss	227	1.7%
Polyneuropathy	226	1.7%
Painpain, site not specified	221	1.6%
Haematotoxicity	220	1.6%
Palmar-plantar erythrodysaesthesia syndrome	210	1.6%
Hypotensionlow blood pressure	209	1.5%
Infectionan infection, type not specified	205	1.5%
Drug intolerancethe medicine was not tolerated	200	1.5%
Condition aggravatedthe condition being treated got worse	192	1.4%
Metastases to liver	192	1.4%
Dizzinesslight-headedness or unsteadiness	188	1.4%
Constipation	181	1.3%
Hypokalaemialow blood potassium	177	1.3%

Download all 963 terms of Leucovorin (CSV)

The counts add to more than 13,519 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 Leucovorin, 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	84	71	11	6	59	1	0	7	13
2005	190	171	29	9	120	3	0	65	19
2006	80	78	10	6	62	2	0	12	2
2007	38	37	13	3	21	1	0	8	1
2008	6	6	0	0	4	1	0	1	0
2009	13	13	4	1	7	0	0	8	0
2010	18	15	2	2	9	1	0	6	3
2011	23	22	9	1	9	0	0	13	1
2012	212	207	53	7	66	0	0	106	5
2013	667	647	113	36	346	8	0	279	20
2014	445	430	77	15	175	3	0	238	15
2015	449	440	108	21	179	6	0	234	9
2016	433	425	95	14	113	3	0	290	8
2017	524	496	110	15	127	3	0	348	28
2018	811	781	109	27	438	11	2	466	30
2019	620	602	91	25	294	4	2	374	18
2020	522	498	76	23	215	9	0	328	24
2021	751	728	125	66	296	5	0	489	23
2022	1,644	1,623	211	161	620	8	3	1,188	21
2023	1,899	1,811	296	141	771	11	1	1,393	88
2024	1,502	1,473	191	92	601	11	0	1,135	29
2025	1,729	1,690	191	169	671	21	4	1,332	39
2026	859	839	156	78	329	29	15	620	20

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 Leucovorin, 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 Leucovorin, by the year in which FDA received them
Year	Reports
2004	63
2005	193
2006	95
2007	35
2008	12
2009	14
2010	18
2011	32
2012	255
2013	698
2014	467
2015	443
2016	467
2017	554
2018	967
2019	687
2020	661
2021	816
2022	1,596
2023	1,757
2024	1,431
2025	1,541
2026	717

Reports that name Leucovorin, 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 Leucovorin
Age	Reports	Share
Under 2	98	0.7%
2 to 11	179	1.3%
12 to 17	131	1%
18 to 44	1,073	7.9%
45 to 64	4,341	32.1%
65 to 74	2,920	21.6%
75 and over	1,060	7.8%
Age not given	3,717	27.5%

Sex of the patient in the reports that name Leucovorin
Sex	Reports	Share
Female	4,291	31.7%
Male	6,277	46.4%
Unknown or not given	2,951	21.8%

Type of reporter in the reports that name Leucovorin
Reporter	Reports	Share
Physician	6,059	44.8%
Pharmacist	557	4.1%
Other health professional	5,766	42.7%
Lawyer	2	under 0.1%
Consumer or non-health professional	786	5.8%
Not given	349	2.6%

Age and sex are as the report gives them. The reporter is the primary source in the report. 27.9% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Leucovorin record
Indication as recorded (MedDRA)	Reports	Share
Colorectal cancer metastatic	2,610	19.3%
Colorectal cancer	880	6.5%
Colon cancer	486	3.6%
Pancreatic carcinoma metastatic	391	2.9%
Pancreatic carcinoma	334	2.5%
Adenocarcinoma of colon	332	2.5%

The reporter fills in the indication, and the field is often empty. Each share is of all 13,519 reports.

Drugs in the same reports

Other drugs that the reports of Leucovorin name, in any role, in order of name
Drug	Reports that name the two
Bevacizumab	2,343
Capecitabine	883
Dexamethasone	1,302
Docetaxel	781
Fluorouracil	9,418
Irinotecan	4,120
Irinotecan hydrochloride	903
Methotrexate	1,070
Ondansetron	715
Oxaliplatin	7,696

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

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Leukeran next in the A to Z list
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These links are for navigation. No count selected them.

Official pages

DailyMed labels for LeucovorinThe 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.

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Reported Reactions. Leucovorin: adverse event reports that FDA received. https://reportedreactions.com/drug/leucovorin/ 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 Leucovorin as a suspect or interacting product. The 9,189 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 Leucovorin 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 Leucovorin?

No. It is a count of what people reported to FDA: 13,519 reports from February 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 (44.8%), other health professional (42.7%) and consumer or non-health professional (5.8%). 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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