The riskiest time is induction (especially the first 2 weeks on methadone, before tolerance is re-established) and when other sedatives are used. Titrate slowly, supervise consumption initially, and warn about benzodiazepine and alcohol interactions.
Methadone
- Full agonist, long half-life (accumulates over days)
- QT prolongation at higher doses (consider an ECG)
- Many interactions; overdose risk in induction
- Daily supervised dosing at first
Buprenorphine
- Partial agonist with a ceiling effect (safer in overdose alone)
- Precipitated withdrawal if given too early: wait for objective moderate withdrawal (for example COWS score) before the first dose
- Less sedation and fewer interactions; blocks other opioids
- Often preferred where a clearer head is needed
Stable maintenance
- Supervised dosing initially
- Methadone titrated slowly
- Review and reduce supervision
Induction risk
- Deaths cluster in the first 2 weeks
- Start low, go slow
- Buprenorphine: wait for withdrawal
Overdose risk
- Sedation, pinpoint pupils, low RR
- Interactions: benzodiazepines, alcohol
- Naloxone, reassess the dose
Key points
1
1. Assess
Confirm dependence (history, examination, urine drug screen). Offer blood-borne virus testing and hepatitis B vaccination.
Confirm dependence (history, examination, urine drug screen). Offer blood-borne virus testing and hepatitis B vaccination.
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2
2. Start
Follow the induction protocol: low starting dose, review before further increases, and supervised consumption. For buprenorphine, wait for withdrawal to avoid precipitating it.
Follow the induction protocol: low starting dose, review before further increases, and supervised consumption. For buprenorphine, wait for withdrawal to avoid precipitating it.
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3
3. Stabilise and support
Titrate to a dose that stops withdrawal and craving. Provide psychosocial support alongside. Relax supervision as the person stabilises.
Titrate to a dose that stops withdrawal and craving. Provide psychosocial support alongside. Relax supervision as the person stabilises.
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4
4. Safety
Safe storage away from children (methadone is lethal to a child), driving advice, and caution with sedatives.
Safe storage away from children (methadone is lethal to a child), driving advice, and caution with sedatives.
Watch for
- Methadone accumulation and overdose in the first days
- Buprenorphine-precipitated withdrawal if started too soon
- Diversion and concurrent benzodiazepine or alcohol use
Pitfalls
- Rapid methadone up-titration
- Starting buprenorphine before withdrawal has begun
- Unsupervised dosing too early
- Ignoring QT risk with high-dose methadone
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026