Reported Reactions

Adverse event reports that FDA received

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Methadone hcl adverse event reports that FDA received

Name type
Generic name

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

From January 2004 to August 2021, FDA received 4,331 adverse event reports that name Methadone hcl. In these reports the drug is a suspect or interacting product.

In the same period, 3,980 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 0 reports in the 12 months to June 2026 and 0 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

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 Methadone hcl 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 1 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 .

No update is on record for this page. The record starts when FDA adds the reports of July to September 2026.

FDA received no report that names Methadone hcl in April to June 2026, in January to March 2026 or in April to June 2025.

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 294 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 4,295 of the 4,331 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.

The table shows the first 50 of 294 terms.

Reaction terms in the reports that name Methadone hcl, most reports first
Reaction term (MedDRA) and plain meaningReportsShare of the 4,331 reports
Toxicity to various agentspoisoning or toxic effect of one or more substances79418.3%
Cardiac arrestthe heart stopped65115%
Respiratory arrestbreathing stopped62814.5%
Completed suicidedeath by suicide54212.5%
Overdosea dose above the recommended amount3337.7%
Drug interactionan interaction between medicines3057%
Cardio-respiratory arrestthe heart and breathing stopped3047%
Drug toxicity3006.9%
Drug abusemisuse of a medicine2425.6%
Deaththe patient died; cause not stated by this term2325.4%
Multiple drug overdose2034.7%
Poisoning1653.8%
Electrocardiogram QT prolongeda QT prolongation on the ECG1593.7%
Respiratory depressionslow or shallow breathing1413.3%
Somnolencedrowsiness1363.1%
Intentional drug misuse1303%
Drug abuser1212.8%
Torsade de pointesa serious irregular heart rhythm1202.8%
Drug dependencedependence on a medicine1132.6%
Drug withdrawal syndrome neonatal1122.6%
Pulmonary oedemafluid in the lungs1042.4%
Loss of consciousnesspassing out992.3%
Drug ineffectivethe medicine did not work as expected922.1%
Drug withdrawal syndromesymptoms on stopping a medicine872%
Foetal exposure during pregnancythe unborn baby was exposed to the medicine852%
Vomitingbeing sick852%
Coma841.9%
Developmental delayslower development in a child831.9%
Accidental overdosean accidental overdose801.8%
Painpain, site not specified791.8%
Multiple drug overdose intentional761.8%
Intentional overdosea deliberate overdose731.7%
Nauseafeeling sick691.6%
Confusional stateconfusion651.5%
Nystagmus641.5%
Pneumonialung infection641.5%
Hypotensionlow blood pressure631.5%
Dyspnoeashortness of breath601.4%
Visual acuity reducedreduced sharpness of vision591.4%
Pulmonary congestion581.3%
Depressed level of consciousness551.3%
Therapeutic agent toxicity551.3%
Agitationrestlessness541.2%
Hyperhidrosisexcessive sweating541.2%
Strabismus541.2%
Congenital nystagmus531.2%
Convulsion521.2%
Drug exposure during pregnancythe medicine was taken during pregnancy521.2%
Sedationdrowsiness521.2%
Drug screen positive511.2%

Download all 294 terms of Methadone hcl (CSV)

The counts add to more than 4,331 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.

Outcomes by year

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

Outcomes in the reports that name Methadone hcl, 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
2004296290199195420666
200535335023367871853
2006318312171428171966
200731930114623831219518
2008577549389389591112728
20093713482731757205723
20103973692508652410228
201166263448524781317828
2012910880655377254019230
2013652130021
2014221000010
2015552010030
2016810000017
201717116070046
2018752121022
2019810010007
2020191750511142
20215655704154531

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 Methadone hcl, by the year in which FDA received them
01,0002,000200420072010201320162019
Show the figures of the chart as a table
Reports that name Methadone hcl, by the year in which FDA received them
YearReports
2004288
2005352
2006317
2007316
2008539
2009394
2010409
2011483
20121,107
20135
20143
20156
201610
201716
20188
20198
202020
202150
Reports that name Methadone hcl, by month, five years to June 2026
051020222023202420252026

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 Methadone hcl
AgeReportsShareShare as a bar
Under 21272.9%
2 to 11671.5%
12 to 17671.5%
18 to 441,98545.8%
45 to 641,06824.7%
65 to 74811.9%
75 and over491.1%
Age not given88720.5%
Sex of the patient in the reports that name Methadone hcl
SexReportsShareShare as a bar
Female1,27929.5%
Male2,04847.3%
Unknown or not given1,00423.2%
Type of reporter in the reports that name Methadone hcl
ReporterReportsShareShare as a bar
Physician1,35531.3%
Pharmacist3528.1%
Other health professional93921.7%
Lawyer300.7%
Consumer or non-health professional88720.5%
Not given76817.7%

Age and sex are as the report gives them. The reporter is the primary source in the report. 67.6% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Methadone hcl record
Indication as recorded (MedDRA)ReportsShare
Pain3117.2%
Drug dependence1212.8%
Back pain831.9%
Drug withdrawal maintenance therapy481.1%
Drug abuser380.9%
Ill-defined disorder350.8%

The reporter fills in the indication, and the field is often empty. Each share is of all 4,331 reports.

Pages near this one

These links are for navigation. No count selected them.

Official pages

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

Cite this page

Reported Reactions. Methadone hcl: adverse event reports that FDA received. https://reportedreactions.com/drug/methadone-hcl/ 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 1 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 Oct 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Methadone hcl as a suspect or interacting product. The 3,980 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 Methadone hcl 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 Methadone hcl?

No. It is a count of what people reported to FDA: 4,331 reports from January 2004 to August 2021. 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 (31.3%), other health professional (21.7%) and consumer or non-health professional (20.5%). 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.