Methadone

Administration

• Type: opioid
• Dosage Forms:
• Routes of Administration: oral, IM/subcutaneous
• Common Trade Names:

Adult Dosing

• Varies widely due to patient variability in ADME, tolerance, indication
• Usual doses:
  • Opioid use disorder, maintenance: 40-120mg/day or higher
  • Pain: initial dose 2.5mg TID for opioid naive

Pediatric Dosing

Safety/efficacy not established in pediatric patients

• 0.1-0.2mg/kg q6h

Special Populations

• Pregnancy Rating: Category C
• Lactation risk: infant risk minimal

Renal Dosing

• Adult: lower initial starting dose

Hepatic Dosing

• Adult: lower initial starting dose

Contraindications

• Allergy to class/drug

Adverse Reactions

Serious

• QTc prolongation
• Torsades de pointes
• Respiratory depression/acidosis/arrest

Common

• Constipation
• Nausea/vomiting
• Sedation
• Dizziness
• Hypotension

Pharmacology

• Half-life: 8-59 hours
• Metabolism: mostly hepatic

Mechanism of Action

• Synthetic opioid