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methadone

Adjunctive therapy

Brands: Methadose, Dolophine

Published 2026-02-15 · Last reviewed 2026-02-22 · 4 references

Content sourced from FDA labeling (DailyMed) and peer-reviewed literature.

Print sheet Review evidence

At a glance

Class: Adjunctive therapy·Typical dose: Opioid use disorder (OUD) dosing is typically managed within an opioid treatment program, with dose changes guided by withdrawal control, cravings, and safety (guideline/clinical).·Half-life: Single-dose range 8–59 h·LAI available: No

Class: Adjunctive therapy
Typical dose: Opioid use disorder (OUD) dosing is typically managed within an opioid treatment program, with dose changes guided by withdrawal control, cravings, and safety (guideline/clinical).
Half-life: Single-dose range 8–59 h
LAI available: No

Quick answers

What is methadone?: Methadone (brands include Methadose and Dolophine; generics) is a long-acting, full opioid agonist used for opioid use disorder (OUD) treatment (in regulated opioid treatment programs) and for analgesia (label).
What is Methadose?: Methadose is a brand name for methadone (other brands: Dolophine).
What is Methadose (methadone) used for?: Label indications include: Opioid use disorder maintenance in certified opioid treatment programs and analgesia (label varies by product).
What drug class is Methadose (methadone)?: Opioid Agonist.
What is the mechanism of action of Methadose (methadone)?: Long-acting full μ-opioid receptor agonist used for opioid use disorder maintenance (in regulated opioid treatment programs) and for analgesia. Long and variable half-life can lead to accumulation and overdose risk if titration is too rapid (label/guideline).
What strengths does Methadose (methadone) come in?: Oral tablets and oral solutions (label; product-specific).

General information

Methadone (brands include Methadose and Dolophine; generics) is a long-acting, full μ-opioid receptor agonist used for opioid use disorder (OUD) treatment (within regulated opioid treatment programs) and for analgesia (label).

In opioid use disorder care, methadone is associated with strong treatment retention and reduced illicit opioid use, but access is shaped by program requirements and early-treatment safety needs (guideline/clinical).

Methadone’s half-life is long and highly variable, creating accumulation risk early in treatment and after dose changes; cautious titration and close early monitoring are emphasized in label and guidance (label/clinical).

QTc prolongation is a key safety concern. Methadone has been associated with torsades de pointes, especially with higher doses or additive risk factors (label/clinical).

The compare view, methadone evidence feed, and methadone print page support counseling when opioid treatment decisions overlap with co-prescribed sedatives and psychiatric comorbidity.

U.S. approvals

Opioid use disorder treatment and analgesia (label; product-specific)

Formulations & strengths

Oral tablets and oral solutions (label; product-specific).

Generic availability

Generic available in the U.S.

Often used in opioid treatment programs when high opioid tolerance is present or when buprenorphine response is insufficient. QTc monitoring and careful coordination with sedating psychiatric medications are common safety considerations.

View labelExact

Mechanism of action

Refer to the Glossary entry on Neurotransmitters for background on receptor systems involved in serious mental illness.

Full μ-opioid receptor agonist producing opioid-agonist effects that suppress withdrawal and cravings in opioid use disorder (OUD) and provide analgesia in pain settings (label).

The long and variable pharmacokinetic profile increases accumulation risk and shapes cautious titration practices (label/clinical).

Full μ-opioid receptor agonism (opioid agonist).

Metabolism & pharmacokinetics

Metabolized hepatically with contributions from CYP enzymes (including CYP2B6 and CYP3A4), with elimination via urine and feces; renal clearance is pH-dependent (label).
Half-life variability is substantial and can be prolonged by interactions and patient factors, contributing to accumulation risk (label/clinical).
Methadone can prolong QTc; risk rises with higher doses, other QT-active medications, and electrolyte abnormalities (label/clinical).

Dosing & administration

Opioid use disorder (OUD) dosing is typically managed within an opioid treatment program, with dose changes guided by withdrawal control, cravings, and safety (guideline/clinical).
Because accumulation risk is highest early in treatment, many programs avoid rapid escalation and reassess frequently after dose changes (label/clinical).
Co-occurring sedatives and interacting medications are commonly reviewed at each step in titration (label/clinical).

Monitoring & labs

Monitor sedation and respiratory status during initiation and after dose increases; reassess concurrent sedatives and polysubstance use risk (label/clinical).
QTc planning: consider ECG monitoring when cardiac risk factors, high doses, or QT-active co-medications are present (label/clinical).
Monitor for constipation and other opioid adverse effects that can affect adherence and quality of life (clinical).
Reassess withdrawal control and cravings and adjust treatment supports (housing, therapy, peer support) when available (guideline/clinical).

Early treatment and medication changes are the highest-risk periods because of accumulation and interaction effects; structured follow-up is common in opioid treatment programs (label/clinical).

Adverse effects

FDA boxed warnings

Common side effects (≥10%)

Sedation / dizziness: Can impair driving and work safety, especially early in treatment or when combined with other sedatives (label/clinical).
Constipation: A common opioid adverse effect; proactive bowel regimens are often discussed in long-term treatment (clinical).
Sweating / sexual dysfunction: Can affect quality of life and retention; clinicians may adjust the plan if symptoms are persistent (clinical).

Other notable effects

Respiratory depression and opioid overdose risk increases with dose escalation, during early treatment, and with other CNS depressants (label/clinical).
QTc prolongation and torsades risk are clinically important; ECG monitoring is often considered when risk factors are present (label/clinical).
Drug interactions can alter exposure and withdrawal control; monitoring often focuses on over-sedation and withdrawal symptoms after regimen changes (label/clinical).

Interactions

CNS depressants (alcohol, benzodiazepines, sedative-hypnotics, gabapentinoids) can increase sedation and respiratory depression risk (label/clinical).
CYP inducers and inhibitors can change methadone exposure; regimen changes often prompt monitoring for withdrawal or over-sedation (label/clinical).
QT-prolonging drugs and electrolyte disturbances can add risk; combined risk review is common in polypharmacy settings (label/clinical).

Other useful information

Guidelines describe methadone as an effective medication for opioid use disorder with strong retention, while emphasizing the need for structured monitoring and program-based access in many jurisdictions (guideline/clinical).
QTc risk is a frequent reason methadone is discussed alongside ECG planning and avoidance of additive QT-active medications when feasible (label/clinical).
In psychiatric care, methadone may interact with antipsychotics and other sedating agents; coordination can reduce additive sedation and QT risk (clinical).

References

Related hubs:SMI toolkit·Support resources