Medication Reference Card: Opioid Use Disorder

Buprenorphine/Naloxone Sublingual

Suboxone® & generic · S8 · PBS s100 · Vic permit · Induction: COWS ≥8–12 · Maintenance: 8–24 mg/day

Dr Basanth Kenchaiah
FRANZCP · Cert. Addiction Psych. · MBBS · DPM · DNB (Psychiatry) Addiction Psychiatrist v1.2 · October 2026

Audience Clinicians

Purpose Prescribing quick-reference for sublingual buprenorphine/naloxone (Suboxone®) in opioid use disorder (OUD), as part of opioid dependence treatment (ODT, also called opioid substitution therapy, OST).

Key messages

Partial mu-agonist with naloxone deterrent: reduces withdrawal, craving and illicit opioid use
Induction when COWS ≥8–12; start 2–4 mg sublingual; titrate to 8–24 mg/day maintenance
Victoria: any medical or nurse practitioner can prescribe with a Schedule 8 permit for each patient, applied for through SafeScript (no prescriber training course required; the 30-patient cap was removed on 14 October 2026); arrange the dispensing pharmacy before starting

For Patients

Buprenorphine is a medication that partially activates opioid receptors, reducing cravings and withdrawal symptoms without producing the high of stronger opioids. The naloxone component discourages misuse by injection. It is taken as a film or tablet under the tongue and can be prescribed by GPs, nurse practitioners and specialists who hold a permit for your treatment.

Particularly useful when comorbid with:

Prescription opioid analgesic dependence (analgesic activity: dual benefit) Chronic pain with opioid use disorder Depression / anxiety (kappa antagonism: antidepressant properties) Pregnancy (mono buprenorphine preferred; consult specialist) Previous overdose / high relapse risk Unable to attend daily methadone dosing

For Clinicians

Mechanism

Buprenorphine: Partial mu-opioid agonist with very high receptor affinity, slow dissociation (long half-life 24–60 hrs), and ceiling effect for respiratory depression. Displaces full agonists: precipitates withdrawal if initiated before patient is in moderate withdrawal (COWS ≥8–12). Naloxone: short-acting antagonist; minimally absorbed sublingually but active if injected (abuse deterrent). Combination produces stable opioid receptor occupancy, eliminates cravings, and blocks the reinforcing effects of additional opioids.

Dosing & Induction

Standard induction: 2–4 mg SL when COWS ≥8–12 (moderate withdrawal). Observe 1 hour, re-dose if tolerated. Titrate to 8–16 mg on day 1. Maintenance: 8–24 mg/day (most patients 12–16 mg/day). Low-dose induction (Bernese method): begin 0.5–1 mg while patient still on full agonist, increase gradually over days; avoids precipitated withdrawal entirely. Doses under 2 mg need buprenorphine (mono) tablets: the Victorian ODT Guidelines advise that films should not be cut or divided. PBS prescriptions: 28 days' supply with up to 5 repeats.

Evidence

Strong evidence. Fudala et al. NEJM 2003: buprenorphine/naloxone significantly superior to placebo for opioid use disorder. NIDA CTN 0003: comparable to methadone for prescription opioid dependence. Lee et al. Lancet 2018 (X:BOT trial): extended-release naltrexone vs buprenorphine: both effective; buprenorphine easier to initiate (lower induction failure rate).

Cautions

Precipitated withdrawal risk: use COWS scale; wait for score ≥8–12 before first dose (or use Bernese method)
QTc prolongation: less concern than methadone, but baseline ECG reasonable in high-risk patients
Concurrent benzodiazepines: significant respiratory depression risk; risk vs benefit discussion, consider supervised dispensing
Victoria: the permit must be issued before the first dose (usually within one working day); check SafeScript at every prescription; 4 or more consecutive missed doses need prescriber review before the next dose; offer take-home naloxone
Hepatotoxicity rare but documented: monitor LFTs at baseline and periodically
In pregnancy: mono buprenorphine (without naloxone) preferred; consult addiction medicine/obstetrics specialist