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Adverse event reports that FDA received

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Tecfidera (dimethyl fumarate) adverse event reports that FDA received

Name type
Brand name
Generic name
Dimethyl fumarate

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.

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

Reports on file

From December 2010 to June 2026, FDA received 114,022 adverse event reports that name Tecfidera. In these reports the drug is a suspect or interacting product.

In the same period, 5,069 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 711 reports in the 12 months to June 2026 and 1,213 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, 711 (0.1%) name Tecfidera. Reports from consumers or other non-health professionals were 78% of the reports that name Tecfidera 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 . The site read the page on .

Suspect product

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

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 .

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 . The site read the page on .

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

  • In April to June 2026, FDA received 146 reports that name Tecfidera.
  • In January to March 2026, FDA received 185.
  • In April to June 2025, FDA received 319.

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 updatesFeed 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 1,730 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 114,022 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.

The table shows the first 50 of 1,730 terms.

Reaction terms in the reports that name Tecfidera, most reports first
Reaction term (MedDRA) and plain meaningReportsShare of the 114,022 reports
Flushingsudden reddening or warmth of the skin16,54214.5%
Nauseafeeling sick8,5857.5%
Diarrhoealoose or frequent stools7,9146.9%
Multiple sclerosis relapsea flare of multiple sclerosis7,5226.6%
Fatiguetiredness6,3565.6%
Gastric disorder5,5244.8%
Vomitingbeing sick5,4294.8%
Multiple sclerosis5,3624.7%
Memory impairmentmemory problems5,3324.7%
Abdominal pain upperupper stomach pain5,2354.6%
Pruritusitching4,8234.2%
Headachehead pain4,6494.1%
Falla fall4,4093.9%
Drug ineffectivethe medicine did not work as expected4,3063.8%
Gait disturbancedifficulty walking3,9823.5%
Malaisegeneral feeling of being unwell3,9453.5%
Abdominal discomfortstomach discomfort3,4793.1%
Painpain, site not specified3,1032.7%
Dizzinesslight-headedness or unsteadiness3,0582.7%
Astheniaweakness or lack of energy2,9692.6%
Hypoaesthesianumbness2,7462.4%
Hot flusha hot flush2,5352.2%
Balance disorderproblems with balance2,4652.2%
Paraesthesiatingling or pins and needles2,4152.1%
Rashskin rash2,3232%
Alopeciahair loss2,2001.9%
Gastrointestinal disorder2,1761.9%
Abdominal painstomach or belly pain2,1301.9%
Urinary tract infectionbladder or urinary infection2,0931.8%
Erythemaskin redness2,0131.8%
Muscle spasmsmuscle cramps1,9641.7%
Depressionlow mood1,8821.7%
Pain in extremitypain in an arm or leg1,8411.6%
Muscular weaknessmuscle weakness1,7751.6%
Mobility decreasedreduced ability to move about1,7741.6%
Dyspepsiaindigestion1,7291.5%
Feeling abnormalfeeling odd or not right1,7181.5%
Prescribed underdose1,7131.5%
Drug dose omissiona dose was missed1,6981.5%
Constipation1,6951.5%
Burning sensationa burning feeling1,6761.5%
White blood cell count decreasedlow white cell count1,6721.5%
Weight decreasedweight loss1,6271.4%
Urticariahives1,5991.4%
Cognitive disorderproblems with thinking or memory1,5591.4%
Feeling hot1,5581.4%
Insomniadifficulty sleeping1,5151.3%
Anxiety1,5091.3%
Seizurea fit or convulsion1,4811.3%
Visual impairmentreduced vision1,4731.3%

Download all 1,730 terms of Tecfidera (CSV)

The counts add to more than 114,022 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 .

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 Dimethyl fumarate with a page, in the order generic names, brand names, names as reported
NameName typeReports
Dimethyl fumarateGeneric name2,761
Tecfidera (this page)Brand name114,022

Sum of the separately reported names: 116,783. 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 .

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 .

Outcomes by year

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

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

The table continues to the right.

Year of the openFDA fileReportsSeriousDeathLife-threateningHospitalization (initial or prolonged)Disability or Permanent DamageCongenital Anomaly/Birth DefectOther Serious (Important Medical Events)Not serious
201313,4108942566187029412,516
201417,6482,852119222,00218382814,796
201512,5184,279219262,8932981,3368,239
201611,8004,429247342,7562081,6467,371
201711,0914,473300282,49626101,9316,618
201811,2764,218264362,33534101,8537,058
20199,9824,134235582,29336151,8945,848
20209,4184,120209402,16242132,0015,298
20216,1012,900124471,54255171,4573,201
20224,7172,047116389452631,1072,670
20232,9151,33255246361887011,583
20241,5487415414324312403807
20251,208618262329192327590
2026390155148729090235

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 .

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 .

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 Tecfidera, by the year in which FDA received them
010,00020,000201020132016201920222025

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 Tecfidera, by the year in which FDA received them
YearReports
20101
20111
20124
201314,340
201417,494
201512,027
201612,640
201711,606
201811,599
201910,106
20209,188
20215,560
20224,278
20232,504
20241,332
20251,011
2026331
Reports that name Tecfidera, by month, five years to June 2026
05001,00020222023202420252026

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 Tecfidera
AgeReportsShareShare as a bar
Under 21440.1%
2 to 1130under 0.1%
12 to 171920.2%
18 to 4419,59417.2%
45 to 6430,69226.9%
65 to 745,1144.5%
75 and over6530.6%
Age not given57,60350.5%
Sex of the patient in the reports that name Tecfidera
SexReportsShareShare as a bar
Female84,66674.3%
Male22,69319.9%
Unknown or not given6,6635.8%
Type of reporter in the reports that name Tecfidera
ReporterReportsShareShare as a bar
Physician12,56811%
Pharmacist2,9892.6%
Other health professional8,9727.9%
Lawyer8under 0.1%
Consumer or non-health professional88,92378%
Not given5620.5%

Age and sex are as the report gives them. The reporter is the primary source in the report. 91.1% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Tecfidera record
Indication as recorded (MedDRA)ReportsShare
Multiple sclerosis89,33278.3%
Relapsing-remitting multiple sclerosis4,4803.9%
Maternal exposure timing unspecified1950.2%
Secondary progressive multiple sclerosis780.1%
Relapsing multiple sclerosis680.1%
Paternal exposure timing unspecified15under 0.1%

The reporter fills in the indication, and the field is often empty. Each share is of all 114,022 reports.

Drugs in the same reports

Other drugs that the reports of Tecfidera name, in any role, in order of name
DrugReports that name the two
Ampyra7,693
Aspirin2,569
Avonex4,713
Baclofen5,315
Ergocalciferol3,203
Gabapentin4,341
Lisinopril1,831
Tysabri2,615
Vitamin B121,663
Vitamin d3,875

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 .

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 .

Pages near this one

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Official pages

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Reported Reactions. Tecfidera: adverse event reports that FDA received. https://reportedreactions.com/drug/tecfidera/ 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.

A report is in the count when it names Tecfidera as a suspect or interacting product. The 5,069 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 Tecfidera 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 . The site read the page on .

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 Tecfidera?

No. It is a count of what people reported to FDA: 114,022 reports from December 2010 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?

Consumer or non-health professional (78%), physician (11%) and other health professional (7.9%). 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 .

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.