METHADONE

85/100 · Critical

Manufactured by VistaPharm, LLC

High Safety Concerns with Methadone Use

88,944 FDA adverse event reports analyzed

Last updated: 2026-05-12

About METHADONE

METHADONE is a medication tracked in the FDA Adverse Event Reporting System (FAERS), manufactured by VistaPharm, LLC. Based on analysis of 88,944 FDA adverse event reports, METHADONE has a safety score of 85 out of 100. This score indicates a relatively favorable safety profile, with fewer or less severe adverse events compared to many other tracked medications. The most commonly reported adverse reactions for METHADONE include DRUG DEPENDENCE, TOXICITY TO VARIOUS AGENTS, DRUG ABUSE, OVERDOSE, PAIN. This page provides a comprehensive breakdown of reported side effects, safety signals, patient demographics, and AI-powered safety analysis for METHADONE.

AI Safety Analysis

Methadone has a safety concern score of 85 out of 100, placing it in the high concern category based on analysis of FDA adverse event data. The FDA has received approximately 88,944 adverse event reports for this medication, which is primarily manufactured by Vistapharm, Llc.

The most commonly reported adverse events include Drug Dependence, Toxicity To Various Agents, Drug Abuse. Of classified reports, 86.3% were designated as serious by the FDA, meaning they involved hospitalization, disability, or other significant medical outcomes. Methadone is associated with a high risk of serious adverse events, including overdose, death, and cardiac arrest.

The drug is frequently reported to cause drug dependence and withdrawal symptoms, both in adults and neonates. Methadone use is linked to significant respiratory depression and respiratory failure, posing a critical risk.

Patients taking Methadone should monitor for the commonly reported side effects and contact their healthcare provider if they experience any unusual symptoms. Methadone can interact with other drugs, potentially leading to increased toxicity or reduced efficacy. Warnings include interactions with drugs that affect the QT interval and central nervous system depressants. This analysis is based on voluntary FDA adverse event reports and should not replace professional medical advice.

Safety Score: 85/100

Methadone received a safety concern score of 85/100 (high concern). This is based on a 86.3% serious event ratio across 41,635 classified reports. The score accounts for 88,944 total adverse event reports and 100 distinct reaction types. This high score reflects a significant proportion of serious adverse events in the reporting data.

Top Adverse Reactions

DRUG DEPENDENCE5,614 reports
TOXICITY TO VARIOUS AGENTS5,213 reports
DRUG ABUSE4,797 reports
OVERDOSE3,842 reports
PAIN3,671 reports
DEATH3,520 reports
EMOTIONAL DISTRESS2,384 reports
DRUG WITHDRAWAL SYNDROME2,343 reports
DRUG INEFFECTIVE1,723 reports
FOETAL EXPOSURE DURING PREGNANCY1,659 reports
NAUSEA1,601 reports
DRUG INTERACTION1,592 reports
ANXIETY1,335 reports
DRUG WITHDRAWAL SYNDROME NEONATAL1,334 reports
FATIGUE1,300 reports
OFF LABEL USE1,270 reports
VOMITING1,253 reports
SOMNOLENCE1,227 reports
COMPLETED SUICIDE1,084 reports
CARDIAC ARREST1,036 reports
DYSPNOEA954 reports
DEPRESSION937 reports
HEADACHE935 reports
DEPENDENCE899 reports
RESPIRATORY DEPRESSION890 reports
PNEUMONIA847 reports
INTENTIONAL PRODUCT MISUSE829 reports
ELECTROCARDIOGRAM QT PROLONGED824 reports
DIARRHOEA808 reports
COMA802 reports
RESPIRATORY ARREST781 reports
CONSTIPATION776 reports
CARDIO RESPIRATORY ARREST753 reports
MALAISE748 reports
DEVELOPMENTAL DELAY723 reports
WITHDRAWAL SYNDROME693 reports
CONFUSIONAL STATE676 reports
FALL667 reports
DEPRESSED LEVEL OF CONSCIOUSNESS661 reports
INSOMNIA649 reports
LEARNING DISABILITY649 reports
ASTHENIA626 reports
MATERNAL EXPOSURE DURING PREGNANCY620 reports
DIZZINESS606 reports
EXPOSURE DURING PREGNANCY595 reports
ARTHRALGIA585 reports
WEIGHT DECREASED579 reports
LOSS OF CONSCIOUSNESS542 reports
DISABILITY541 reports
HYPERHIDROSIS537 reports
PYREXIA535 reports
ABDOMINAL PAIN521 reports
POISONING511 reports
DELIRIUM505 reports
BACK PAIN504 reports
PAIN IN EXTREMITY492 reports
HYPOTENSION491 reports
ACCIDENTAL OVERDOSE479 reports
ACUTE KIDNEY INJURY471 reports
FEELING ABNORMAL460 reports
PULMONARY OEDEMA458 reports
SUICIDAL IDEATION447 reports
DECREASED APPETITE442 reports
HYPERTENSION435 reports
CONDITION AGGRAVATED431 reports
TREMOR429 reports
SUBSTANCE ABUSE420 reports
RASH419 reports
AGITATION418 reports
RESPIRATORY FAILURE414 reports
WEIGHT INCREASED409 reports
UNRESPONSIVE TO STIMULI408 reports
MENTAL DISORDER395 reports
MIOSIS390 reports
SEIZURE387 reports
TORSADE DE POINTES383 reports
SUICIDE ATTEMPT365 reports
ANAEMIA364 reports
ABDOMINAL PAIN UPPER360 reports
MUSCLE SPASMS358 reports
GAIT DISTURBANCE355 reports
RENAL FAILURE350 reports
TACHYCARDIA350 reports
PRODUCT USE ISSUE346 reports
DRUG HYPERSENSITIVITY343 reports
CHEST PAIN341 reports
INJURY325 reports
INTENTIONAL OVERDOSE324 reports
MEMORY IMPAIRMENT323 reports
SEDATION323 reports
PRODUCT USE IN UNAPPROVED INDICATION319 reports
DRUG USE DISORDER306 reports
DRUG DIVERSION297 reports
PNEUMONIA ASPIRATION291 reports
OEDEMA PERIPHERAL289 reports
HALLUCINATION288 reports
PRURITUS288 reports
SEROTONIN SYNDROME288 reports
CHRONIC KIDNEY DISEASE287 reports
RHABDOMYOLYSIS280 reports

Key Safety Signals

  • Overdose and death are the most serious adverse events, with high report volumes.
  • Cardiac arrest and respiratory depression are critical safety signals, indicating potential life-threatening risks.
  • Neonatal withdrawal syndrome is a key safety signal, highlighting the risks to infants exposed to methadone during pregnancy.

Patient Demographics

Adverse event reports by sex: Male: 20,594, Female: 16,434, Unknown: 174. The most frequently reported age groups are age 55 (693 reports), age 39 (655 reports), age 47 (642 reports). These demographics reflect reporting patterns and may not represent the full patient population.

Report Outcomes

Out of 41,635 classified reports for METHADONE:

  • Serious: 35,937 reports (86.3%) — includes hospitalization, disability, life-threatening events, or death
  • Non-Serious: 5,698 reports (13.7%)
Serious 86.3%Non-Serious 13.7%

The FDA classifies an adverse event as “serious” if it results in death, hospitalization, disability, congenital anomaly, or requires intervention to prevent permanent damage.

Demographics Breakdown

Reports by Sex

Male20,594 (55.4%)
Female16,434 (44.2%)
Unknown174 (0.5%)

Reports by Age

Age 55693 reports
Age 39655 reports
Age 47642 reports
Age 37641 reports
Age 32640 reports
Age 40629 reports
Age 35618 reports
Age 43616 reports
Age 34583 reports
Age 54579 reports
Age 31563 reports
Age 44562 reports
Age 49555 reports
Age 50554 reports
Age 48550 reports
Age 45536 reports
Age 38523 reports
Age 51519 reports
Age 41518 reports
Age 33513 reports

Demographics reflect voluntary FDA adverse event reporting patterns and may not represent the full patient population.

Drug Interactions & Warnings

Methadone can interact with other drugs, potentially leading to increased toxicity or reduced efficacy. Warnings include interactions with drugs that affect the QT interval and central nervous system depressants.

What You Should Know

If you are taking Methadone, here are important things to know. The most commonly reported side effects include drug dependence, toxicity to various agents, drug abuse, overdose, pain. While many of these may be mild and temporary, you should contact your healthcare provider if any symptoms are severe or persistent. Patients should strictly follow prescribed dosages and avoid self-adjustment of medication. Regular monitoring by healthcare providers is essential to manage potential side effects and adjust treatment as necessary. If you experience a serious adverse reaction, seek emergency medical attention immediately or call 911. You can report side effects to the FDA's MedWatch program at 1-800-FDA-1088.

Regulatory Context

The FDA closely monitors methadone use due to its high safety concerns. Healthcare providers should be vigilant in monitoring patients for signs of adverse reactions and adjust dosages accordingly.

Frequently Asked Questions

How many adverse event reports has the FDA received for Methadone?

The FDA has received approximately 88,944 adverse event reports associated with Methadone. These reports come from healthcare professionals, consumers, and manufacturers through the FDA Adverse Event Reporting System (FAERS). Note that the number of reports does not directly indicate the frequency of side effects, as adverse events are voluntarily reported and may be underrepresented.

What are the most commonly reported side effects of Methadone?

The most frequently reported adverse events for Methadone include Drug Dependence, Toxicity To Various Agents, Drug Abuse, Overdose, Pain. By volume, the top reported reactions are: Drug Dependence (5,614 reports), Toxicity To Various Agents (5,213 reports), Drug Abuse (4,797 reports). These figures reflect FDA adverse event reports and may not represent the true incidence rate of these side effects in all patients taking Methadone.

What percentage of Methadone adverse event reports are serious?

Out of 41,635 classified reports, 35,937 (86.3%) were classified as serious and 5,698 as non-serious. The FDA classifies an event as "serious" if it results in death, hospitalization, disability, or other medically significant outcomes. A higher serious-event ratio warrants closer attention but does not necessarily mean the drug is unsafe.

Who reports adverse events for Methadone (by sex)?

Adverse event reports for Methadone break down by patient sex as follows: Male: 20,594, Female: 16,434, Unknown: 174. This distribution reflects reporting patterns rather than actual risk differences between groups. Reporting rates can be influenced by prescribing patterns, disease demographics, and reporting behavior.

What age groups report the most side effects for Methadone?

The most frequently reported age groups for Methadone adverse events are: age 55: 693 reports, age 39: 655 reports, age 47: 642 reports, age 37: 641 reports, age 32: 640 reports. Age-related reporting patterns can reflect both the demographics of the patient population and potential age-related susceptibility to certain side effects.

Who manufactures Methadone?

The primary manufacturer associated with Methadone adverse event reports is Vistapharm, Llc. Multiple manufacturers may produce generic versions of this drug. The manufacturer listed reflects the most frequently reported brand in FDA adverse event data.

What other side effects have been reported for Methadone?

Beyond the most common reactions, other reported adverse events for Methadone include: Death, Emotional Distress, Drug Withdrawal Syndrome, Drug Ineffective, Foetal Exposure During Pregnancy. Less common side effects can still be clinically significant. Patients should report any unusual symptoms to their healthcare provider.

How do I report a side effect from Methadone?

You can report adverse events from Methadone to the FDA through their MedWatch program at www.fda.gov/medwatch, by calling 1-800-FDA-1088, or by completing Form FDA 3500. Healthcare professionals, consumers, and manufacturers can all submit reports. Reporting helps the FDA monitor drug safety after approval.

What is Methadone's safety score and what does it mean?

Methadone has a safety concern score of 85 out of 100 (high concern). This score is calculated from the ratio of serious to non-serious adverse events, the diversity of reported reactions, and the overall volume of reports relative to usage. Methadone is associated with a high risk of serious adverse events, including overdose, death, and cardiac arrest.

What are the key safety signals for Methadone?

Key safety signals identified in Methadone's adverse event data include: Overdose and death are the most serious adverse events, with high report volumes.. Cardiac arrest and respiratory depression are critical safety signals, indicating potential life-threatening risks.. Neonatal withdrawal syndrome is a key safety signal, highlighting the risks to infants exposed to methadone during pregnancy.. These signals are derived from patterns in FDA reports and should be discussed with a healthcare provider for personalized assessment.

Does Methadone interact with other drugs?

Methadone can interact with other drugs, potentially leading to increased toxicity or reduced efficacy. Warnings include interactions with drugs that affect the QT interval and central nervous system depressants. Always inform your healthcare provider about all medications, supplements, and over-the-counter drugs you are taking before starting Methadone.

What should patients know before taking Methadone?

Patients should strictly follow prescribed dosages and avoid self-adjustment of medication. Regular monitoring by healthcare providers is essential to manage potential side effects and adjust treatment as necessary.

Are Methadone side effects well-documented?

Methadone has 88,944 adverse event reports on file with the FDA. The drug is frequently reported to cause drug dependence and withdrawal symptoms, both in adults and neonates. The volume of reports for Methadone reflects both the drug's usage level and the vigilance of the reporting community.

What is the FDA's position on Methadone?

The FDA closely monitors methadone use due to its high safety concerns. Healthcare providers should be vigilant in monitoring patients for signs of adverse reactions and adjust dosages accordingly. For the most current regulatory information, check the FDA's drug labeling database or consult your pharmacist.

Related Drugs

Drugs related to METHADONE based on therapeutic use, drug class, or shared indications:

AmiodaroneLithiumCimetidine
Important Disclaimer: This content is generated by AI analysis of FDA adverse event reports and is provided for informational purposes only. It is not medical advice. Adverse event reports submitted to the FDA do not prove that a medication caused the reported side effect. Always consult your healthcare provider before starting, stopping, or changing any medication. If you experience a serious side effect, contact your doctor or call 911 immediately.