1. Clinical & Scientific Overview
Methadone Hydrochloride (TIP-MED-000523, Reference Code [R-04]) is classified under
Palliative Cancer Pain & Opioid Agonist Therapy as a Synthetic Long-Acting Mu-Opioid Agonist & NMDA Antagonist.
Within the Indian regulatory and compendial framework, it is governed under Essential Narcotic Drug (END — NDPS 2015 Amendment).
Methaddict (Rusan Pharma), Dolophine Reference Standard (Hospital Narcotic Supply)
Oral Syrup/Solution: 5 mg/mL, 10 mg/mL; Oral Tablet: 5 mg, 10 mg, 20 mg, 40 mg
Statutory Restriction, High-Alert & Dispensing Safeguards
Indian Regulatory & Statutory Control Basis: Essential Narcotic Drug (END — NDPS 2015 Amendment)
High-Alert Clinical Risk, Dependence & Narrow Therapeutic Index Warnings: Variable inter-individual half-life leads to delayed cumulative respiratory depression 3–5 days after initiation or dose escalation; dose-dependent hERG potassium channel blockade causes QTc prolongation and Torsades de Pointes.
Mandatory Dispensing Register & Institutional Custody Protocol: Dispensed strictly through State Drug Controller approved Recognized Medical Institutions (RMIs) under END rules; baseline and 30-day ECG QTc monitoring required.
3. Mechanism of Action & Pharmacodynamics
Full mu-opioid receptor agonist with non-competitive NMDA glutamate receptor antagonism and hepatic CYP2B6/CYP3A4 metabolism resulting in a biphasic elimination half-life (15–60 hours).
4. Therapeutic Indications & Evidence-Supported Uses
- Refractory neuropathic and somatic cancer pain in Registered Medical Institutions (RMIs)
- Opioid maintenance therapy
5. Educational Dosage Context, Formulations & Administration
Educational Dosing & Regimen Summary: Specialist-Supervised Educational Reference Summary: Dosing of Methadone must be individualised by a qualified specialist according to clinical indication, organ function, and institutional protocol (Oral Syrup/Solution: 5 mg/mL, 10 mg/mL; Oral Tablet: 5 mg, 10 mg, 20 mg, 40 mg).
Administration & Meal Timing: Routes: Oral. Dispensed strictly through State Drug Controller approved Recognized Medical Institutions (RMIs) under END rules; baseline and 30-day ECG QTc monitoring required.
6. Pharmacokinetics, Metabolism & Renal/Hepatic Adjustment
Exhibits synthetic long-acting mu-opioid agonist & nmda antagonist pharmacokinetic disposition; verify baseline renal and hepatic clearance and check for active or prolonged-half-life metabolites before repeat dosing.
Hepatic Phase I (CYP450) and/or Phase II conjugation or specific non-renal clearance as detailed in clinical warnings.
Verify eGFR / CrCl before initiation; see specific metabolite and renal clearance notes above.
Assess baseline Child-Pugh status and hepatic transaminases prior to therapy.
7. Contraindications, Precautions & High-Risk Warnings
- Known severe hypersensitivity to Methadone or formulation excipients
- Unsupervised outpatient self-administration or dispensing without mandatory statutory prescription verification
- Specific clinical contraindications detailed under High-Alert Warnings & Statutory Restrictions
Key Clinical Precautions: Variable inter-individual half-life leads to delayed cumulative respiratory depression 3–5 days after initiation or dose escalation; dose-dependent hERG potassium channel blockade causes QTc prolongation and Torsades de Pointes.
8. Adverse Effects Profile
- Variable inter-individual half-life leads to delayed cumulative respiratory depression 3–5 days after initiation or dose escalation; dose-dependent hERG potassium channel blockade causes QTc prolongation and Torsades de Pointes.
- Dose-dependent target-organ pharmacodynamic effects requiring clinical observation
- Variable inter-individual half-life leads to delayed cumulative respiratory depression 3–5 days after initiation or dose escalation; dose-dependent hERG potassium channel blockade causes QTc prolongation and Torsades de Pointes.
- High-alert toxicity, dependence/diversion risk, or severe organ-specific adverse events if administered outside protocol
9. Major Drug–Drug, Drug–Food & Drug–Herb Interactions
- Variable inter-individual half-life leads to delayed cumulative respiratory depression 3–5 days after initiation or dose escalation; dose-dependent hERG potassium channel blockade causes QTc prolongation and Torsades de Pointes.
- Review all concomitant CNS depressants, QTc-prolonging agents, nephrotoxins, or CYP450 modulators prior to dispensing.
10. Clinical Monitoring, Patient Counselling & Storage
Clinical & Laboratory Monitoring: Dispensed strictly through State Drug Controller approved Recognized Medical Institutions (RMIs) under END rules; baseline and 30-day ECG QTc monitoring required.
Pharmacist Patient Counselling Points:
- Dispensed strictly through State Drug Controller approved Recognized Medical Institutions (RMIs) under END rules; baseline and 30-day ECG QTc monitoring required.
- Must be used strictly under direct medical supervision; never share prescription medicines or alter the prescribed dose.
Storage, Stability & Dispensing Safeguards: Dispensed strictly through State Drug Controller approved Recognized Medical Institutions (RMIs) under END rules; baseline and 30-day ECG QTc monitoring required.
11. Visual Pharmacology & Mechanism Diagram (svg-v339-01-adme-12-step-journey)
12. Authoritative References, Regulatory Sources & Editorial Disclaimer
Primary Compendial & Guideline Reference: Drugs and Cosmetics Act, 1940 & Rules, 1945 (Schedule H / H1 / X); NDPS Act, 1985 & Essential Narcotic Drugs (END) Notification; Indian Pharmacopoeia (IP) & National Formulary of India (NFI).
Official Verification Portals: CDSCO — Drugs & Cosmetics Act and Rules (Schedules H, H1, X) • Department of Revenue — Narcotic Drugs and Psychotropic Substances (NDPS) Act • Indian Pharmacopoeia Commission (IPC) — National Formulary of India
Last Medically & Pharmaceutically Reviewed: 2026-11-10 • Verification Status: VERIFIED_EDUCATIONAL_CONTENT
Educational & Clinical Disclaimer: This reference profile is published solely for pharmacy education, academic study, and professional clinical reference. It does not substitute for patient-specific clinical judgement, qualified specialist oncology/medical supervision, or official CDSCO/IP prescribing information. Never self-medicate with prescription, Schedule H/H1/X, NDPS, or oncology medicines.