Flecainide adverse event reports that FDA received

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

Name type: Product name as reported
Also reported as: Flecainide /00627102/

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 September 2005 to June 2026, FDA received 3,466 adverse event reports that name Flecainide. The name is as reporters wrote it. In these reports the drug is a suspect or interacting product.

In the same period, 6,802 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 279 reports in the 12 months to June 2026 and 340 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, 279 (under 0.1%) name Flecainide. Reports from consumers or other non-health professionals were 12.3% of the reports that name Flecainide 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 Flecainide 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 57 reports that name Flecainide.
In January to March 2026, FDA received 57.
In April to June 2025, FDA received 87.

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 327 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 3,458 of the 3,466 reports (99.8%).

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 327 terms.

Reaction terms in the reports that name Flecainide, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 3,466 reports
Toxicity to various agentspoisoning or toxic effect of one or more substances	637	18.4%
Drug ineffectivethe medicine did not work as expected	391	11.3%
Drug interactionan interaction between medicines	321	9.3%
Electrocardiogram QRS complex prolonged	320	9.2%
Bradycardiaslow heart rate	265	7.6%
Hypotensionlow blood pressure	253	7.3%
Electrocardiogram QT prolongeda QT prolongation on the ECG	247	7.1%
Cardiac arrestthe heart stopped	230	6.6%
Atrial fibrillationan irregular heart rhythm	227	6.5%
Completed suicidedeath by suicide	218	6.3%
Ventricular tachycardiaa fast rhythm from the lower heart chambers	215	6.2%
Off label useused for a purpose or in a way not on the label	170	4.9%
Foetal exposure during pregnancythe unborn baby was exposed to the medicine	166	4.8%
Dizzinesslight-headedness or unsteadiness	153	4.4%
Overdosea dose above the recommended amount	150	4.3%
Tachycardiafast heart rate	146	4.2%
Arrhythmia	134	3.9%
Intentional overdosea deliberate overdose	132	3.8%
Syncopefainting	129	3.7%
Treatment failurethe treatment did not work	118	3.4%
Acute kidney injurysudden loss of kidney function	113	3.3%
Dyspnoeashortness of breath	108	3.1%
Cardiogenic shockshock from the heart failing to pump	104	3%
Nauseafeeling sick	98	2.8%
Atrioventricular block first degree	96	2.8%
Atrial flutter	92	2.7%
Bundle branch block right	92	2.7%
Fatiguetiredness	88	2.5%
Cardio-respiratory arrestthe heart and breathing stopped	84	2.4%
Maternal exposure during pregnancythe mother took the medicine during pregnancy	76	2.2%
Suicide attempta suicide attempt	75	2.2%
Premature babya baby born early	74	2.1%
Palpitationsawareness of the heartbeat	71	2%
Sinus bradycardia	68	2%
Deaththe patient died; cause not stated by this term	66	1.9%
Exposure during pregnancythe medicine was taken during pregnancy	63	1.8%
Astheniaweakness or lack of energy	62	1.8%
Torsade de pointesa serious irregular heart rhythm	61	1.8%
Product use in unapproved indicationused for a purpose not on the label	59	1.7%
Falla fall	57	1.6%
Electrocardiogram abnormal	56	1.6%
Medication errora mistake in prescribing, dispensing or taking a medicine	54	1.6%
Ventricular fibrillationa chaotic rhythm from the lower heart chambers	54	1.6%
Drug level increaseda raised blood level of the medicine	53	1.5%
Brugada syndrome	51	1.5%
Malaisegeneral feeling of being unwell	51	1.5%
Accidental overdosean accidental overdose	50	1.4%
Supraventricular tachycardia	48	1.4%
Diarrhoealoose or frequent stools	47	1.4%
Bundle branch block left	46	1.3%

Download all 327 terms of Flecainide (CSV)

The counts add to more than 3,466 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 Flecainide, 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
2005	3	3	2	1	2	0	0	1	0
2009	2	2	0	0	2	0	0	1	0
2010	22	21	6	3	11	1	0	7	1
2011	12	11	2	2	6	0	0	5	1
2012	26	24	1	4	10	0	0	17	2
2013	81	66	6	9	32	1	0	43	15
2014	113	96	31	2	48	1	1	46	17
2015	114	91	29	11	32	4	0	44	23
2016	130	124	13	34	55	2	2	74	6
2017	185	170	27	38	78	6	0	115	15
2018	267	249	23	42	133	3	2	185	18
2019	330	302	52	62	168	6	1	224	28
2020	310	299	82	41	187	1	1	206	11
2021	322	300	56	42	185	6	2	214	22
2022	301	274	36	36	116	4	8	199	27
2023	348	326	40	53	184	3	0	214	22
2024	346	317	37	81	178	2	1	221	29
2025	412	395	41	75	189	7	4	322	17
2026	142	131	42	24	64	1	0	80	11

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 Flecainide, 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 Flecainide, by the year in which FDA received them
Year	Reports
2005	3
2009	2
2010	22
2011	15
2012	32
2013	85
2014	107
2015	120
2016	152
2017	199
2018	284
2019	363
2020	324
2021	335
2022	300
2023	354
2024	340
2025	315
2026	114

Reports that name Flecainide, 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 Flecainide
Age	Reports	Share
Under 2	165	4.8%
2 to 11	77	2.2%
12 to 17	78	2.3%
18 to 44	420	12.1%
45 to 64	555	16%
65 to 74	670	19.3%
75 and over	682	19.7%
Age not given	819	23.6%

Sex of the patient in the reports that name Flecainide
Sex	Reports	Share
Female	1,830	52.8%
Male	1,201	34.7%
Unknown or not given	435	12.6%

Type of reporter in the reports that name Flecainide
Reporter	Reports	Share
Physician	1,276	36.8%
Pharmacist	255	7.4%
Other health professional	1,442	41.6%
Lawyer	1	under 0.1%
Consumer or non-health professional	425	12.3%
Not given	67	1.9%

Age and sex are as the report gives them. The reporter is the primary source in the report. 48.1% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Flecainide record
Indication as recorded (MedDRA)	Reports	Share
Atrial fibrillation	908	26.2%
Supraventricular tachycardia	212	6.1%
Arrhythmia	209	6%
Atrial tachycardia	87	2.5%
Tachycardia foetal	81	2.3%
Ventricular tachycardia	65	1.9%

The reporter fills in the indication, and the field is often empty. Each share is of all 3,466 reports.

Drugs in the same reports

Other drugs that the reports of Flecainide name, in any role, in order of name
Drug	Reports that name the two
Amiodarone	344
Apixaban	203
Bisoprolol	291
Digoxin	256
Diltiazem	134
Eliquis	188
Furosemide	154
Metoprolol	444
Propranolol	190
Sotalol	203

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

Flecaine next in the A to Z list
Flecainide acetate next in the A to Z list
Flebogamma Dif next in the A to Z list
Flector next in the A to Z list
Flebogamma next in the A to Z list
Flexeril next in the A to Z list
Flagyl next in the A to Z list
Flixabi next in the A to Z list
Fish oil next in the A to Z list
Flixotide next in the A to Z list
Firmagon next in the A to Z list
Flolan next in the A to Z list

These links are for navigation. No count selected them.

Official pages

DailyMed labels for FlecainideThe 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. Flecainide: adverse event reports that FDA received. https://reportedreactions.com/drug/flecainide/ 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 Flecainide as a suspect or interacting product. The 6,802 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 Flecainide 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 Flecainide?

No. It is a count of what people reported to FDA: 3,466 reports from September 2005 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?

Other health professional (41.6%), physician (36.8%) and consumer or non-health professional (12.3%). 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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