Opioid use disorder — assessment, overdose, and OAT (MEQ)

(i) Overdose and post-naloxone care. Treat as ABC emergency: airway positioning, assisted ventilation/oxygen as needed, monitoring, glucose. Naloxone is titrated to adequate ventilation, not necessarily full alertness — further parenteral doses (typical teaching increments 0.4–2 mg IV/IM, repeated) if hypoventilation returns; remember fentanyl/long-acting agonists may need repeated dosing or infusion. Observe for re-sedation. After revival he is in precipitated/spontaneous withdrawal — manage supportively, avoid punitive discharge. Document time-course, co-ingestants, and prior OAT.[1][5]

(ii) Withdrawal and restart choice. COWS 16 is moderate withdrawal (band 13–24), so he is a candidate for buprenorphine induction now if last full-agonist timing and clinical picture support it — still confirm last use and watch for residual intoxication. Restarting methadone 70 mg immediately after a 3-month gap is unsafe: tolerance is lost; re-induction must be low and slow (often day-1 10–30 mg range with careful review), not automatic return to prior maintenance dose. Benzodiazepines raise OD risk on either OAT pathway.[2][3][5]

(iii) OAT and harm reduction plan (example). Prefer same-episode MOUD: e.g. buprenorphine–naloxone start 2–4 mg SL, reassess 1–2 h, build toward ~8 mg day 1 if tolerated, then titrate toward maintenance 8–24 mg with clinic linkage (ED-initiated pathway evidence). Alternatively specialist methadone re-induction if patient preference/prior response and logistics favour it. Supply take-home naloxone, overdose education, supervised early dosing per local rules, UDS for engagement, BBV pathway already flagged by HCV Ab. Psychosocial offer (keyworking, MI, housing). Avoid arbitrary short detox-only plan.[3][5][6]

(iv) HCV, benzos, partner. Arrange HCV RNA confirmatory testing and linkage to antiviral treatment; harm-reduction injecting advice if still injecting. Address diazepam: quantity, dependence, taper plan, avoid unsupervised sedative polypharmacy with OAT. Partner pregnancy: confidential safeguarding assessment, offer her antenatal care and, if she uses opioids, OAT pathway; child-protection thresholds if risks to unborn/other children — least restrictive, statute-local, non-stigmatising.[5]

(v) Mortality counselling. Explain that retention in opioid agonist treatment is associated with lower mortality, and that risk rises after stopping treatment (Sordo meta-analysis; pharmacotherapy cohorts). “Detox and done” often returns people to use at lost tolerance, which is a high-fatality window. Frame OAT as evidence-based medical treatment, not moral failure.[4]