Methadone

Category: alkaloid

Pharmacological Mechanism

Synthetic μ-opioid agonist + NMDA antagonist + monoamine reuptake inhibition. Long, variable half-life (8–60 h) supports once-daily dosing for opioid use disorder. QT prolongation requires baseline ECG.

Half-Life (t½)

PO: 37h, IV: 37h

Dosing Guidelines

• PO: Typical 30 mg (Range: 2.5–120 mg)

Target Organ Systems

• nervous

Pathways It Modulates

• Opioid receptor signaling (activator) — μ-opioid receptor + NMDA antagonist

Chemical Identifiers

• PubChem CID: 4095
• Formula: C21H27NO
• Molecular weight: 309.45 g/mol
• InChIKey: USSIQXCVUWKGNF-UHFFFAOYSA-N
• SMILES: CCC(=O)C(CC(C)N(C)C)(C1=CC=CC=C1)C2=CC=CC=C2

References

• PMID 9354306