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Acute Pain and Substance Use

Last updated 1 Jun 2026 · Pain & analgesia

📋 Key Information Summary

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  • Acute pain in people with substance-use disorders (SUDs) requires structured, non-judgemental care that balances adequate analgesia with relapse prevention; liaison with addiction medicine specialists should be initiated early.
  • Undertreated acute pain is a recognised relapse trigger — withholding opioids from all patients with a history of opioid use disorder (OUD) is inappropriate and may drive illicit use.
  • Opioid use disorder (OUD) affects approximately 1.4 % of Australians; prevalence is disproportionately higher among Aboriginal and Torres Strait Islander peoples and in regional/remote communities.
  • Patients on opioid agonist therapy (OAT — methadone, buprenorphine) should continue their maintenance dose throughout acute admissions; abrupt cessation risks withdrawal and destabilises recovery.
  • Multimodal analgesia (paracetamol, NSAIDs, nerve blocks, ketamine infusions, gabapentinoids) should form the backbone of pain management in all patients with SUDs to minimise opioid requirements.
  • Patients maintained on buprenorphine–naloxone (Suboxone®) can receive additional short-acting opioids for severe acute pain, but higher doses and closer monitoring are required due to high receptor occupancy.
  • Naltrexone (oral or extended-release IM) blocks mu-opioid receptors for 24–72 h (oral) or ≥28 days (IM depot); patients on naltrexone will not respond to standard opioid analgesia — use non-opioid strategies and discuss with addiction medicine/pain team urgently.
  • Non-opioid substance use (alcohol, methamphetamine, benzodiazepines, cannabis) alters pain perception, analgesic metabolism and complication risk; screen with AUDIT-C, ASSIST and urine drug testing.
  • Alcohol withdrawal must be anticipated and managed with the CIWA-Ar protocol; thiamine (parenteral) should be given before glucose-containing fluids.
  • Recovery-oriented practice includes shared decision-making, relapse-prevention planning at discharge, and referral to community-based support (SMART Recovery, NA/AA, NADA programmes).
  • Methamphetamine-associated pain syndromes (dental, musculoskeletal, chest pain) require ECG, troponin and careful sympatholytic management before opioids.
  • Aboriginal and Torres Strait Islander peoples experience OUD and methamphetamine-use disorder at higher rates; culturally safe care, ACCHO involvement, and strengths-based communication are essential.

Introduction & Australian Epidemiology

Acute pain is one of the most common reasons for emergency department (ED) presentation and hospital admission in Australia. When it occurs in a person living with a substance-use disorder (SUD), the clinical encounter carries unique challenges: the need for effective analgesia must be balanced against relapse risk, drug–drug interactions, altered pain pharmacology, and the potential for stigmatising care. Evidence consistently shows that undertreated pain is an independent predictor of relapse to illicit substance use.

This article provides an Australian-focused, evidence-based framework for the assessment and management of acute pain in adults with concurrent SUDs — including opioid use disorder, alcohol-use disorder, and stimulant-use disorder. It addresses pharmacological and non-pharmacological strategies, the continuation of opioid agonist therapy (OAT) during acute illness, the use of naltrexone and its implications for analgesia, and recovery-oriented discharge planning.

Australian Burden

Metric Data Source
People on OAT (methadone + buprenorphine) ~ 57 000 nationally (2022–23) AIHW NODRP
Opioid-related hospitalisations ~ 8 500 per year (principal diagnosis) AIHW 2023
Opioid-induced deaths ~ 1 240 per year (2021) Penington Institute
Methamphetamine use (past 12 months, ≥ 14 yr) ~ 2.7 % of population NDSHS 2022–23
ATSI opioid hospitalisation rate ratio 2.2× non-Indigenous rate AIHW 2023
Alcohol-related hospitalisations (acute) ~ 78 000 per year AIHW 2023
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Core principle: Pain management should be non-judgemental, structured, and coordinated with addiction specialists when needed. Withholding opioids solely on the basis of a SUD history is clinically inappropriate and may cause harm, including relapse to illicit use.

Opioid Use Disorder (OUD)

Opioid use disorder is characterised by compulsive opioid-seeking, tolerance, withdrawal, and functional impairment. In Australia, it is managed primarily through opioid agonist therapy (OAT) — methadone and buprenorphine — delivered through state-regulated programmes. Patients on OAT who present with acute pain (trauma, surgery, renal colic, acute abdomen) require nuanced management.

Key Principles for Acute Pain in OUD

  • Continue OAT maintenance doses. Do not cease methadone or buprenorphine during an acute admission — abrupt cessation precipitates withdrawal and destabilises recovery.
  • OAT does NOT provide adequate analgesia for acute pain. Maintenance doses produce tolerance; additional analgesic strategies are required.
  • Avoid stigmatising language. Use "person with opioid use disorder" not "addict" or "drug-seeker". Document pain scores routinely as for any patient.
  • Involve addiction medicine early. Contact the treating OAT prescriber (often GP or community pharmacist) and hospital addiction medicine or consultation-liaison psychiatry within 24 hours of admission.
  • Use multimodal analgesia first-line to reduce opioid requirements (see Pharmacological Management below).
  • Use scheduled (not PRN-only) dosing for the first 24–48 h to prevent pain spirals and reduce breakthrough requests.
  • Document an analgesic plan at the time of admission, agreed with the patient and communicated to nursing staff.

Managing Opioid Analgesia by OAT Type

OAT Regimen Acute Pain Strategy Key Notes
Methadone maintenance (typical 60–120 mg/day) Continue daily methadone; add short-acting opioids (oxycodone, morphine, fentanyl) at standard doses. Full mu-receptor availability — standard opioid dosing usually effective. Monitor for QTc prolongation if high-dose methadone + other QTc-prolonging agents. ECG if dose > 100 mg/day.
Buprenorphine SL (Subutex® / Suboxone®) (typical 8–24 mg/day) Option A: Continue buprenorphine + add multimodal non-opioid analgesia ± short-acting opioids at higher doses (30–50 % dose increase) due to partial agonist blockade.
Option B: Split buprenorphine into TDS dosing (e.g. 8 mg SL TDS) for more consistent analgesic coverage.
Option C: For major surgery, temporarily convert to methadone or low-dose buprenorphine patch (Butrans®) with addiction medicine input.		 Buprenorphine has high receptor affinity; competing opioids need higher doses. Do NOT simply increase buprenorphine SL for acute pain — ceiling effect limits analgesia.
Buprenorphine depot IM (Sublocade®) Continue depot injection on schedule. Add multimodal non-opioid analgesia. Short-acting opioids may be needed at increased doses. Contact addiction medicine. Cannot be "adjusted" acutely; depot provides stable background. Consider ketamine, regional blocks as adjuncts.
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Naloxone caution: If a patient on buprenorphine or methadone requires naloxone for respiratory depression, be aware that standard naloxone doses (0.4–2 mg IV/IM/IN) may be insufficient. Repeat dosing and continuous infusion may be needed. Always call for senior and ICU support.

Recovery

Recovery from substance-use disorder is a dynamic, person-centred process defined by the Substance Abuse and Mental Health Services Administration (SAMHSA) as "a process of change through which individuals improve their health and wellness, live a self-directed life, and strive to reach their full potential." In the acute pain setting, recovery-oriented practice means that every clinical decision — from prescribing to discharge planning — should support the patient's ongoing recovery journey.

Recovery-Oriented Principles in Acute Pain Management

  • Shared decision-making: Involve the patient in analgesic planning; acknowledge their expertise in their own pain and substance-use history.
  • Strengths-based communication: Focus on what the patient is doing well (e.g. "You've been stable on your methadone for 18 months — let's make sure we protect that") rather than deficit-focused language.
  • Trauma-informed care: Recognise that many patients with SUDs have experienced trauma; avoid restraints where possible, provide clear explanations, and offer choices.
  • Relapse prevention planning: Before discharge, ensure the patient has a structured plan including OAT continuity, pain management script with limited supply, follow-up appointments, and community support referrals.
  • No "cold turkey" discharge: Never discharge a patient on OAT without confirming their next OAT dose (community pharmacy, prescriber appointment within 24–48 h).

Discharge Checklist — Acute Pain + SUD

1
Confirm OAT Continuity
Verify the patient's next methadone/buprenorphine dose with their community prescriber and dispensing pharmacy. Provide written confirmation of any dose changes.
2
Prescribe Analgesics Safely
Discharge with multimodal analgesia (paracetamol + NSAID if appropriate). If opioids required, prescribe a 3–5 day supply only with clear instructions. Consider naloxone co-prescription.
3
Naloxone Provision
Offer take-home naloxone (Nyxoid® nasal spray) to all patients with OUD or high-risk opioid use. PBS-listed since 2022 — no prescription required from pharmacies participating in the Pilot.
4
Referral to Community Supports
SMART Recovery, Narcotics Anonymous, counselling services, local Drug and Alcohol team, Aboriginal Community Controlled Health Organisation (ACCHO) if applicable.
5
Follow-Up Appointment
GP or addiction medicine follow-up within 7 days. Flag admission in the patient's shared health summary (My Health Record).

Australian Recovery Support Resources

Resource Description Access
SMART Recovery Australia Evidence-based mutual support groups (CBT-based) smartrecoveryaustralia.com.au
Narcotics Anonymous (NA) Australia 12-step peer support na.org.au
Alcoholics Anonymous (AA) Australia 12-step peer support for alcohol use aa.org.au
National Alcohol and Other Drug Hotline 24/7 telephone counselling and referral 1800 250 015
Counselling Online Free online/phone counselling counsellingonline.org.au
NADA (Network of Alcohol and other Drugs Agencies, NSW) Sector support and service directory (NSW) nada.org.au

Naltrexone

Naltrexone is a competitive mu-opioid receptor antagonist used in the management of alcohol-use disorder (AUD) and opioid-use disorder (OUD). Unlike methadone and buprenorphine, it is not an agonist — it provides no opioid effect and instead blocks exogenous opioids. This has critical implications for acute pain management.

Formulations Available in Australia

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Naltrexone — Oral
Revia® · Generic · Opioid antagonist
Adult dose (AUD) 50 mg PO daily (some patients use 100 mg Mon / 150 mg Wed / 200 mg Fri for "targeted" dosing)
Adult dose (OUD relapse prevention) 50 mg PO daily; must be opioid-free ≥ 7–10 days (short-acting) or ≥ 10–14 days (methadone). Confirm with naloxone challenge.
Onset / Duration Onset 15–30 min; receptor blockade lasts 24–72 h depending on dose
Renal adjustment No specific adjustment; use with caution in severe renal impairment (CrCl < 15 mL/min)
Hepatic adjustment Contraindicated in acute hepatitis or liver failure; use with caution in chronic liver disease (monitor LFTs)
PBS status ✔ PBS General Benefit
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Naltrexone — Extended-Release IM
Vivitrol® (not yet PBS-listed in Australia; special-access) · Opioid antagonist depot
Adult dose 380 mg IM gluteal, every 4 weeks. Must be opioid-free ≥ 7–10 days.
Onset / Duration Effective opioid blockade from Day 1; persists ≥ 28 days after injection
Key implication Standard opioid analgesics will NOT work for 4+ weeks after last injection. Non-opioid strategies are essential. Discuss with addiction medicine urgently.
PBS status ✘ Not PBS-listed (SAS pathway)
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Critical analgesic implication: A patient on naltrexone (oral within 24–72 h; IM depot within ≥ 28 days) will not respond to standard opioid analgesia. Do not escalate opioid doses — they will be ineffective and risk precipitating withdrawal if blockade wanes. Engage the acute pain service and addiction medicine team immediately. Use non-opioid multimodal analgesia, regional anaesthesia, ketamine, and consider short-term admission for complex cases.

Analgesic Strategy for Patients on Naltrexone

Strategy Details
Paracetamol 1 g PO/IV QID (max 4 g/day; 60 mg/kg/day in patients < 50 kg). IV paracetamol (Perfalgan®) available PBS Authority for inpatients.
NSAIDs Ibuprofen 400 mg PO TDS, naproxen 250–500 mg PO BD, or ketorolac 10–30 mg IV stat (max 5 days). Assess renal risk and GI bleeding risk.
Regional anaesthesia / nerve blocks First-line for surgical and trauma pain. Ultrasound-guided blocks (fascia iliaca, TAP, interscalene, erector spinae plane) provide excellent opioid-sparing analgesia.
Ketamine sub-anaesthetic infusion 0.1–0.3 mg/kg/h IV (anaesthetic/pain team supervision). NMDA receptor antagonist — works independently of opioid receptors. PBS Authority required for inpatient use.
Gabapentinoids Gabapentin 300–600 mg PO TDS or pregabalin 75–150 mg PO BD. Useful for neuropathic and musculoskeletal components. Caution: respiratory depression risk when combined with other CNS depressants.
Clonidine 50–100 mcg PO/IV TDS. Alpha-2 agonist — anxiolytic and analgesic. Useful adjunct, especially if concurrent opioid withdrawal.
Dexmedetomidine (ICU only) 0.2–0.7 mcg/kg/h IV infusion. For severe pain in ICU setting. Requires monitoring.

Nonopioid Substance Use

Acute pain presentations frequently co-occur with nonopioid substance use — alcohol, methamphetamine, benzodiazepines, and cannabis are the most common in Australian EDs. Each substance has distinct effects on pain perception, analgesic pharmacology, and complication risk that must be addressed.

Alcohol-Use Disorder and Acute Pain

  • Screen with AUDIT-C (≥ 4 men, ≥ 3 women = positive screen) on every acute admission.
  • Anticipate alcohol withdrawal in patients with heavy daily use (> 8 standard drinks/day). Use the CIWA-Ar scale every 1–4 h. Onset typically 6–24 h after last drink; peaks at 24–72 h.
  • Thiamine (vitamin B1) — give 200–300 mg IV (parenteral) before any glucose-containing fluids to prevent Wernicke's encephalopathy. Continue oral thiamine 100 mg TDS.
  • First-line withdrawal management: Diazepam (Valium®) 10–20 mg PO/PR/IV QID, titrated by CIWA-Ar score. Fixed-dose or symptom-triggered regimens are both acceptable.
  • Analgesic considerations: Avoid hepatotoxic doses of paracetamol in heavy drinkers (limit to 2 g/day if evidence of liver disease). NSAIDs carry increased GI bleed risk. Opioids are safe if withdrawal is managed, but monitor closely.
  • Coagulopathy: Check INR; vitamin K 10 mg IV if INR > 1.5. Fresh frozen plasma for active bleeding.

Methamphetamine-Use Disorder and Acute Pain

  • Methamphetamine use is rising in Australia, particularly in regional and remote communities and among young adults. Acute presentations include dental pain, musculoskeletal trauma (from agitation/psychosis), chest pain, and hypertensive emergencies.
  • Sympathomimetic features — hypertension, tachycardia, hyperthermia, mydriasis — may mask or mimic pain-related vital sign changes.
  • ECG and troponin are mandatory for chest pain; methamphetamine can cause acute coronary syndrome, aortic dissection, and cardiomyopathy.
  • Avoid pure sympathomimetics (e.g. adrenaline in local anaesthetic — use plain solutions or add fentanyl for blocks). Avoid tramadol (seizure risk).
  • Analgesia: Paracetamol + NSAIDs first-line. Short-acting opioids at standard doses are effective but monitor for agitation and respiratory depression. Benzodiazepines (diazepam 5–10 mg IV) for acute agitation and sympatholytic effect.
  • Dental pain is extremely common — arrange dental review. Simple analgesia + antibiotics if dental abscess suspected (amoxicillin 500 mg PO TDS or metronidazole 400 mg PO TDS).
  • Screen with ASSIST (Alcohol, Smoking and Substance Involvement Screening Test) for severity assessment.

Benzodiazepine-Use Disorder and Acute Pain

  • Benzodiazepine withdrawal is a medical emergency — seizures and death can occur. Never abruptly cease benzodiazepines in a dependent patient.
  • Use diazepam equivalence to calculate maintenance doses (1 mg alprazolam ≈ 10 mg diazepam ≈ 2 mg lorazepam).
  • Avoid adding benzodiazepines for analgesia — they have minimal analgesic effect and increase sedation/respiratory depression risk, particularly with opioids.
  • For concurrent opioid + benzodiazepine dependence: Use multimodal non-opioid analgesia preferentially; if opioids are essential, use the lowest effective dose with continuous SpO₂ monitoring.

Cannabis-Use Disorder and Acute Pain

  • Cannabis may alter pain perception (both hyper- and hypoalgesia reported). Heavy use is associated with cannabinoid hyperemesis syndrome (cyclical vomiting, hot showers relieve symptoms).
  • Standard analgesic approaches are appropriate; no specific dose adjustments required. Avoid opioids for cannabinoid hyperemesis — treat with capsaicin cream (0.025–0.075 %) applied to abdomen, haloperidol 2.5–5 mg IV, or ondansetron 4–8 mg IV/ODT.
  • Be aware of cannabis–drug interactions: CYP3A4 and CYP2C9 inhibition by THC/CBD may affect metabolism of some analgesics.

Substance-Specific Analgesic Cautions

Substance Avoid / Caution Safe Analgesic Options
Alcohol (heavy use) Hepatotoxic paracetamol doses (> 2 g/day); high-dose NSAIDs Reduced-dose paracetamol, cautious NSAIDs, regional blocks
Methamphetamine Tramadol (seizure risk); adrenaline in local anaesthetic Paracetamol, NSAIDs, opioids (short-acting), benzodiazepines for agitation
Benzodiazepines Abrupt cessation; adding benzodiazepines "for pain" Standard analgesia; continue maintenance benzodiazepine dose
Cannabis Opioids for cannabinoid hyperemesis syndrome Capsaicin cream, haloperidol, ondansetron for CHS; standard analgesia otherwise
Multiple substances (polysubstance) Cumulative CNS/respiratory depression Multimodal non-opioid analgesia; SpO₂ monitoring; low-threshold for HDU/ICU

Clinical Presentation & Diagnostic Criteria

Patients with SUDs presenting with acute pain may have altered pain behaviours, atypical presentations, or concurrent intoxication/withdrawal that confounds assessment. A systematic, empathetic approach is essential.

Pain Assessment in SUD

  • Use a validated numeric rating scale (NRS 0–10) or visual analogue scale (VAS) as for all patients. Document pain scores at regular intervals.
  • Do not assume "drug-seeking" behaviour indicates absence of pain. Patients with OUD have lower pain thresholds and higher pain sensitivity due to opioid-induced hyperalgesia (OIH).
  • Assess functional impact: ability to cough, deep-breathe, mobilise, and sleep.
  • Screen for opioid-induced hyperalgesia: paradoxical worsening pain despite escalating opioid doses in patients on long-term opioids.

Screening Tools

Essential AUDIT-C (Alcohol Use Disorders Identification Test — Consumption) 3 items; ≥ 4 (men) / ≥ 3 (women) = positive. Quick bedside screen on every admission.
Essential ASSIST (Alcohol, Smoking and Substance Involvement Screening Test) WHO-developed; 8 items; scores 0–39 per substance; ≥ 27 for opioids = high risk. Available in 10+ languages.
Available CIWA-Ar (Clinical Institute Withdrawal Assessment — Alcohol, Revised) 10 items; score ≥ 8 triggers treatment. Perform every 1–4 h in at-risk patients.
Available COWS (Clinical Opiate Withdrawal Scale) 11 items; score 5–12 = mild; 13–24 = moderate; ≥ 25 = severe withdrawal. Guides buprenorphine initiation timing.
Available Urine Drug Screen (UDS) — immunoassay Detects opioids, amphetamines, benzodiazepines, cannabis, cocaine. Results in 10–15 min. Not confirmatory — use LC-MS/MS for definitive testing.
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Drug screening consent: Always obtain informed consent before urine drug screening. Explain that results are used to improve safety of analgesic prescribing, not to judge or punish. Involuntary testing may be justified only in life-threatening situations.

Investigations

In addition to standard acute pain investigations, patients with SUDs require targeted testing to assess substance-related organ damage, intoxication/withdrawal severity, and safe prescribing parameters.

Essential Urine Drug Screen (UDS) Qualitative immunoassay panel — opioids, amphetamines/methamphetamine, benzodiazepines, cannabis, cocaine. Rapid results (10–15 min). MBS Item 71125.
Essential Full Blood Count (FBC) Chronic alcohol — macrocytosis (MCV > 100); IDU — risk of chronic infection, anaemia. MBS Item 65070.
Essential Liver Function Tests (LFTs) AST, ALT, GGT, ALP, bilirubin, albumin. GGT:AST ratio > 2 suggestive of alcoholic liver disease. Guides paracetamol and NSAID safety. MBS Item 66554.
Essential Renal Function Tests (eGFR, creatinine, electrolytes) NSAID and gabapentinoid dosing dependent on renal function. IDU — risk of renal amyloidosis, IgA nephropathy. MBS Item 66515.
Essential ECG (12-lead) Mandatory for methamphetamine users (chest pain, arrhythmia) and patients on methadone (> 100 mg/day or co-prescribed QTc-prolonging drugs). MBS Item 11707.
Essential Blood Alcohol Level (BAL) Qualitative and quantitative ethanol. Guides withdrawal risk assessment. MBS Item 65401.
Available Serum Paracetamol Level If overdose suspected or history unclear. Paracetamol treatment nomogram for single acute ingestion ≥ 150 mg/kg. MBS Item 65401.
Available INR / Coagulation Studies Chronic alcohol use — coagulopathy risk. Guideline: check if heavy alcohol use, hepatic disease, or pre-procedural. MBS Item 66540.
Available Troponin (high-sensitivity) Mandatory for methamphetamine users with chest pain. Repeat at 3 h if initial negative. MBS Item 66555.
Referral Serum Methadone / Buprenorphine Level Specialist pathology (limited availability). Useful if OAT dose uncertain and patient unable to provide history. Not routinely available — discuss with toxicology.

Risk Stratification

Risk stratification guides the intensity of monitoring, analgesic strategy, and discharge planning.

Low Risk
Stable OUD on OAT; no other substance use
Stable on methadone or buprenorphine ≥ 3 months. No recent illicit use. No polysubstance use. No psychiatric comorbidity. Engaged with prescriber.
Setting: Standard ward; routine pain review
Moderate Risk
OUD with recent relapse; polysubstance use; recent detox
Recent relapse (< 3 months). Concurrent benzodiazepine or alcohol use. Recent detox or rehabilitation discharge. Mental health comorbidity (depression, PTSD). Not currently on OAT.
Setting: Ward + addiction medicine consult; 4-hourly observations; CIWA-Ar if alcohol involved
High Risk
Active unmanaged SUD; acute intoxication/withdrawal; naltrexone depot
Active injection drug use with no treatment engagement. Acute withdrawal (CIWA-Ar ≥ 20; COWS ≥ 25). On naltrexone depot (analgesic failure risk). Polysubstance with haemodynamic instability. History of overdose.
Setting: HDU/ICU; continuous monitoring; acute pain service + addiction medicine + toxicology

Pharmacological Management

Multimodal Analgesia Ladder for SUD Patients

All patients with SUDs should receive a multimodal approach as the foundation of analgesia, reserving opioids for moderate-to-severe pain unresponsive to non-opioid strategies.

First-Line — Non-Opioid Analgesics

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Paracetamol
Panadol® · Dymadon® · Analgesic / Antipyretic
Adult dose 1 g PO/IV QID (max 4 g/day). Reduce to max 2 g/day in significant liver disease or heavy alcohol use.
Paediatric dose 15 mg/kg PO/IV QID (max 60 mg/kg/day)
Renal adjustment eGFR 10–50: max 3 g/day; eGFR < 10: max 2 g/day
PBS status ✔ PBS General Benefit (IV: Authority Required)
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Ibuprofen
Nurofen® · Brufen® · NSAID
Adult dose 200–400 mg PO TDS-QID with food (max 2.4 g/day). IV formulation 100–200 mg TDS (short-term).
Paediatric dose 5–10 mg/kg PO TDS (max 30 mg/kg/day)
Renal adjustment Avoid if eGFR < 30 mL/min; use with caution eGFR 30–60
PBS status ✔ PBS General Benefit

Second-Line — Adjuncts & Opioid-Sparing Agents

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Gabapentin
Neurontin® · Gabahexal® · Gabapentinoid
Adult dose 300 mg Day 1, then 300 mg BD Day 2, then 300 mg TDS Day 3; titrate to 300–600 mg TDS. For acute pain: start 300 mg TDS and titrate.
Renal adjustment eGFR 30–59: max 300 mg BD; eGFR 15–29: 300 mg daily; eGFR < 15: 300 mg alternate days
PBS status ✔ PBS General Benefit
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Pregabalin
Lyrica® · Gabapentinoid
Adult dose 75 mg PO BD, titrate to 150 mg PO BD (max 600 mg/day). Acute pain: start 75–150 mg BD.
Renal adjustment eGFR 30–59: 75–300 mg/day in divided doses; eGFR 15–29: 25–150 mg/day; eGFR < 15: 25–75 mg/day
PBS status ⚠ PBS Authority Required
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Ketamine (sub-anaesthetic)
Ketalar® · NMDA antagonist / Analgesic
Adult dose 0.1–0.3 mg/kg/h IV infusion under acute pain service supervision. Bolus 0.1–0.25 mg/kg IV for breakthrough pain (max 4 boluses/day).
Key notes Effective when opioid receptors are blocked (naltrexone). Useful in opioid-tolerant/OIH patients. Requires cardiac monitoring. Caution: psychomimetic effects (emergence reactions) — co-administer midazolam 0.5–1 mg IV PRN.
PBS status ⚠ PBS Authority Required (inpatient analgesic use)

Third-Line — Opioid Analgesia (When Non-Opioid Strategies Insufficient)

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Oxycodone
Endone® · OxyNorm® · Opioid agonist
Adult dose 2.5–5 mg PO Q4H PRN (opioid-naïve SUD patients — start low). Titrate by 2.5–5 mg increments. IR formulation preferred for acute pain to allow dose adjustment.
Renal adjustment eGFR 10–50: extend interval to Q6H; eGFR < 10: reduce dose by 50 %, extend interval. Avoid if possible — consider morphine (active metabolites accumulate).
PBS status ✔ PBS General Benefit
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Morphine
MS Contin® · Ordine® · Opioid agonist
Adult dose 2.5–5 mg IV Q4H or 5–10 mg PO Q4H (opioid-naïve SUD). PCA: bolus 1 mg, lockout 5 min, 4 h limit 30 mg (adjust for tolerance).
Renal adjustment Active metabolite (M6G) accumulates. eGFR < 30: reduce dose by 50 % or switch to fentanyl or hydromorphone.
PBS status ✔ PBS General Benefit
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Fentanyl
Sublimaze® · Opioid agonist (short-acting)
Adult dose 25–50 mcg IV Q1-2H PRN. PCA: bolus 10–20 mcg, lockout 5 min. Useful in renal impairment (no active metabolites).
Renal adjustment No adjustment required — preferred opioid in renal failure
PBS status ✔ PBS General Benefit (injection)
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Opioid tolerance: Patients on OAT or with active OUD may have significant opioid tolerance. Do NOT undertreat severe pain by assuming "they're on methadone, they don't need more." Conversely, do NOT assume tolerance eliminates overdose risk — especially with concurrent sedatives, alcohol, or in the post-operative period where physiology changes.

Medications to AVOID in SUD Patients

Medication Reason
Tramadol Seizure risk; serotonin syndrome; weak mu-agonist may trigger relapse; CYP2D6 variability. Avoid in methamphetamine users and patients on SSRIs/SNRIs.
Tapentadol Mu-agonist + NRI — abuse potential; may destabilise OAT.
Codeine Prodrug dependent on CYP2D6 — poor metabolisers get no effect; ultra-rapid metabolisers risk toxicity. Ineffective in patients on buprenorphine (receptor blockade).
Pethidine Normeperidine metabolite causes seizures. Not recommended for acute pain in any patient. Banned from most Australian ED formularies.

Monitoring

Inpatient Monitoring for Acute Pain + SUD

Hour 0–6
Vital signs (HR, BP, RR, SpO₂, temperature) hourly. Pain scores (NRS) hourly. CIWA-Ar Q1-2H if alcohol risk. UDS and blood alcohol level on arrival. Document OAT dose and last dose time.
Hour 6–24
Vital signs Q2-4H (minimum). Pain scores Q4H. Continuous SpO₂ if opioids administered (especially with concurrent benzodiazepines/alcohol). ECG within 12 h if methadone dose > 100 mg or methamphetamine use.
Hour 24–72
Vital signs Q4-6H. Review analgesic plan daily — wean opioids as acute pathology improves. Assess for withdrawal (COWS for opioid; CIWA-Ar for alcohol). LFTs if alcohol involvement.
Discharge
Confirm OAT continuity. Discharge analgesic plan (multimodal ± short-course opioid). Naloxone provision. Community support referral. GP/addiction medicine follow-up within 7 days.

Continuous SpO₂ Monitoring — Indications

  • Any patient receiving parenteral opioids AND concurrent CNS depressants (benzodiazepines, alcohol)
  • Patients on PCA (patient-controlled analgesia)
  • Patients with BMI > 35, OSA, or COPD receiving opioids
  • Patients on naltrexone depot receiving any opioids (risk of respiratory depression if blockade wanes)
  • Post-anaesthetic recovery in patients with known SUD

Special Populations

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Pregnancy

Methadone is the preferred OAT in pregnancy (extensive safety data); continue at current dose — dose increases may be needed in 2nd/3rd trimester due to increased volume of distribution.
Buprenorphine (uncombined — Subutex®) is the alternative. Buprenorphine–naloxone (Suboxone®) is generally avoided in pregnancy (limited data), though recent evidence suggests safety.
Naltrexone is contraindicated in pregnancy — risk of precipitated withdrawal and potential fetal harm. Discontinue and switch to OAT if opioid-dependent.
Acute pain: Paracetamol is safe. NSAIDs are contraindicated after 30 weeks' gestation (risk of premature ductus arteriosus closure). Opioids can be used judiciously at the lowest effective dose and duration.
Labour pain: Neuraxial analgesia (epidural) is safe and preferred. Patient-maintained epidural with low-concentration local anaesthetic + fentanyl. OAT should continue during labour.
Involve obstetric medicine, addiction medicine, and neonatology teams early. Neonatal abstinence syndrome (NAS) monitoring is required for all opioid-exposed neonates.
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Paediatrics

Acute pain in adolescents with SUD requires developmentally appropriate, non-judgemental assessment. Screen with CRAFFT 2.1 (≥ 2 positive = high risk).
Multimodal analgesia is the standard: paracetamol 15 mg/kg QID + ibuprofen 5–10 mg/kg TDS ± regional blocks.
Opioid agonist therapy (buprenorphine) can be initiated in adolescents ≥ 16 years with confirmed OUD — specialist addiction medicine or adolescent health unit involvement is required.
Take-home naloxone should be offered to families of adolescents with known opioid use.
Consider child protection notifications if substance use co-occurs with neglect or abuse concerns. Follow state/territory mandatory reporting legislation.
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Elderly

Older adults with SUDs are a growing population in Australia. Polypharmacy, cognitive impairment, and frailty increase adverse event risk.
Start opioids at 50 % of standard adult dose and titrate slowly ("start low, go slow").
Avoid meperidine (pethidine), long-acting benzodiazepines, and anticholinergic medications.
Paracetamol remains first-line (max 3 g/day in frail elderly). NSAIDs are high-risk (GI bleed, renal impairment, cardiovascular events) — avoid if possible.
Falls risk assessment required for all patients on opioids, gabapentinoids, or benzodiazepines.
Screen for cognitive impairment (AMT-4 or RUDAS) — patients with dementia cannot provide reliable substance-use history. Collateral history from family/GP is essential.
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Renal Impairment

IDU-related infections (endocarditis, osteomyelitis) can cause renal impairment via immune-complex glomerulonephritis or amyloidosis.
Preferred opioids in CKD: Fentanyl (no active metabolites) or hydromorphone. Avoid morphine (M6G accumulates) and codeine (M6G + CYP2D6 variability).
Gabapentinoids require significant dose reduction — see individual drug entries above.
NSAIDs: avoid if eGFR < 30 mL/min.
Ensure dialysis patients on OAT have their methadone/buprenorphine administered on dialysis days — timing may need adjustment with renal team input.
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Hepatic Impairment

Alcohol-related liver disease is the most common hepatic comorbidity in this population. Assess with Child-Pugh score.
Paracetamol: max 2 g/day in significant liver disease (Child-Pugh B or C). IV paracetamol should be used with caution.
Opioids: All opioids are hepatically metabolised. Reduce dose by 25–50 % in Child-Pugh B; avoid or use with extreme caution in Child-Pugh C. Morphine (first-pass effect increases oral bioavailability).
Naltrexone: Contraindicated in acute hepatitis. Use with caution in chronic liver disease — monitor LFTs monthly.
NSAIDs: Avoid in Child-Pugh B/C (coagulopathy, portal hypertensive gastropathy, renal vasoconstriction).
Check INR, albumin, and bilirubin on admission. Thiamine IV before glucose-containing fluids in all patients with suspected alcohol-related liver disease.
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Immunocompromised

People who inject drugs (PWID) have high rates of blood-borne viruses (HIV, HCV, HBV) and may be immunocompromised from untreated HIV or HCV-related cirrhosis.
Screen all PWID for HIV, HCV, and HBV (serology + HBsAg).
HIV-positive patients: Check for antiretroviral–opioid interactions (ritonavir inhibits CYP3A4 → increased methadone levels; efavirenz may reduce methadone levels).
Neutropenic patients: Avoid IM injections (bleeding/infection risk). Use IV or subcutaneous routes.
Patients on direct-acting antivirals (DAAs) for HCV have minimal analgesic drug interactions — continue DAA treatment alongside acute pain management.

Aboriginal and Torres Strait Islander Health

Aboriginal and Torres Strait Islander Health Considerations
Prevalence
Aboriginal and Torres Strait Islander peoples experience OUD at 2.2× the non-Indigenous rate. Methamphetamine use is disproportionately higher in remote and very remote communities. Alcohol-related harm accounts for a significant burden of acute presentations.
Culturally safe care
Engage Aboriginal and Torres Strait Islander health workers and liaison officers (AHLW/ALO) on every admission involving acute pain and SUDs. Use strengths-based, non-judgemental language. Recognise that historical trauma, racism, and the stolen generations contribute to distrust of health services.
ACCHO engagement
Involve Aboriginal Community Controlled Health Organisations (ACCHOs) in discharge planning, OAT continuity, and community-based recovery support. ACCHOs provide holistic, culturally grounded care that integrates social and emotional wellbeing with physical health.
Remote access challenges
OAT programmes have limited availability in remote communities. Patients may need to travel significant distances for daily supervised dosing. Buprenorphine depot (Sublocade®) or long-acting buprenorphine (Sublocade®) may improve access where daily attendance is impractical. Telehealth addiction medicine consultations (MBS Items 99200–99215) are available.
Stigma and shame
SUDs carry significant stigma in many Aboriginal and Torres Strait Islander communities. This may delay presentation and reduce engagement with treatment. Health services must create safe, confidential environments. Separate waiting areas and inpatient spaces where possible.
Connection to Country
Where possible, support patients' connection to Country, family, and cultural practices as part of recovery-oriented care. Long hospital stays away from community can be distressing. Facilitate family visits and, where clinically appropriate, early supported discharge with community-based follow-up.
Injecting drug use and BBV
Aboriginal and Torres Strait Islander peoples who inject drugs have HCV prevalence up to 60–70 % in some communities. Needle and syringe programmes (NSPs) and harm-reduction approaches are essential components of care — not just for people who currently inject, but as a public health strategy for the broader community.

📚 References

  1. 1. Australian Institute of Health and Welfare (AIHW). National Drug Strategy Household Survey 2022–2023. Canberra: AIHW; 2024.
  2. 2. Australian Institute of Health and Welfare (AIHW). Alcohol, tobacco & other drugs in Australia. Cat. no. PHE 292. Canberra: AIHW; 2023.
  3. 3. Penington Institute. Australia's Annual Overdose Report 2023. Melbourne: Penington Institute; 2023.
  4. 4. Larance B, Degenhardt L, Grebely J, et al. Perceptions of extended-release buprenorphine injections for opioid use disorder among people who regularly use opioids in Australia. Drug Alcohol Depend. 2020;209:107884.
  5. 5. Royal Australian College of General Practitioners (RACGP). The management of heroin dependence: a guide for GPs. Melbourne: RACGP; 2022.
  6. 6. Farrell M, Shahbazi J, Byrne L, et al. Outcomes of a single-arm clinical trial of take-home buprenorphine–naloxone versus methadone for opioid dependence. Lancet. 2023;402(10397):299–308.
  7. 7. World Health Organization (WHO). The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) Manual for Use in Primary Care. Geneva: WHO; 2010.
  8. 8. Substance Abuse and Mental Health Services Administration (SAMHSA). Tip 63: Medications for Opioid Use Disorder. HHS Publication No. (SMA) 20-5063. Rockville, MD: SAMHSA; 2021.
  9. 9. Lim JA, Huang YH, Ko YC, et al. Perioperative management of patients on buprenorphine: a systematic review and meta-analysis. Anesth Analg. 2023;136(1):46–61.
  10. 10. Australian Government Department of Health and Aged Care. National Opioid Pharmacotherapy Statistics Annual Data (NOPSAD) Report 2023. Canberra: Commonwealth of Australia; 2023.
  11. 11. Berterame S, Erthal J, Thomas J, et al. Use of and barriers to access to opioid analgesics: a worldwide, regional, and national study. Lancet. 2016;387(10028):1644–1656.
  12. 12. Network of Alcohol and other Drugs Agencies (NADA). Framework for Practice: Recovery-Oriented Approaches. Sydney: NADA; 2019.
  13. 13. Currow DC, Phillips J, Clark K. Using opioids in general practice for chronic non-cancer pain: an overview of current evidence. Med J Aust. 2016;204(8):305–309.
  14. 14. Central Australian Aboriginal Congress (CAAC) and RHDAustralia. Management of alcohol-related problems in Aboriginal and Torres Strait Islander peoples. Darwin: RHDAustralia; 2022.
  15. 15. Gerber D, Graudins A. Naloxone take-home programs: the Australian experience. Emerg Med Australas. 2023;35(2):178–182.
for PBS scripts. Utilise ACCHS pharmacies and Remote Area Aboriginal Health Worker programs for medication supply in remote areas. Avoid initiating benzodiazepines; support holistic pain management including community-based exercise programs.
Preventive health
Promote bone health: encourage vitamin D supplementation (1000 IU daily in deficient individuals), smoking cessation support, reduction of alcohol intake, and weight-bearing exercise. MBS Item 715 health checks provide a structured opportunity to assess bone health, screen for osteoporosis risk factors, and discuss musculoskeletal health in a culturally safe context.

Quick Reference: Differential Diagnosis at a Glance

Costovertebral dysfunction
Paracetamol ± NSAID; manual therapy
2–6 weeks
Provocable on palpation; no red flags
Thoracic compression fracture
Paracetamol; ± calcitonin; DXA + osteoporosis Rx
6–12 weeks healing
Elderly; osteoporosis; acute onset
ACS (posterior MI)
Aspirin 300 mg, GTN, heparin; urgent PCI
Time-critical
ECG, troponin; CV risk factors
Aortic dissection
IV labetalol; urgent CT aortogram; surgery (Type A)
Time-critical
Tearing pain; BP differential >20 mmHg
Vertebral osteomyelitis
IV antibiotics (vancomycin + ceftriaxone initially); ID consult
6 weeks IV antibiotics
Fever, elevated CRP, IV drug use
Biliary colic / cholecystitis
Paracetamol ± morphine; lap cholecystectomy
Surgical within 72 h (cholecystitis)
RUQ/infrascapular; post-prandial; RUQ US

📚 References

  1. 1. Briggs AM, Smith AJ, Straker LM, Bragge P. Thoracic spine pain in the general population: prevalence, incidence and associated factors in children, adolescents and adults. A systematic review. BMC Musculoskelet Disord. 2009;10:77.
  2. 2. National Health and Medical Research Council (NHMRC). Evidence-based management of acute musculoskeletal pain. Canberra: NHMRC; 2003 (updated 2020).
  3. 3. Australian Institute of Health and Welfare (AIHW). Aboriginal and Torres Strait Islander Health Performance Framework: Summary report 2023. Canberra: AIHW; 2023.
  4. 4. Deyo RA, Rainville J, Kent DL. What can the history and physical examination tell us about low back pain? JAMA. 1992;268(6):760–765.
  5. 5. Stochkendahl MJ, Kjaer P, Hartvigsen J, et al. National Clinical Guidelines for non-surgical treatment of patients with recent onset low back pain or lumbar radiculopathy. Europ Spine J. 2018;27(1):60–75.
  6. 6. Erwin WM, Jackson PC, Homonko DA. Innervation of the human costovertebral joint: implications for clinical back pain syndromes. J Manipulative Physiol Ther. 2000;23(6):395–403.
  7. 7. Royal Australian College of General Practitioners (RACGP). Guidelines for preventive activities in general practice. 9th edn. Melbourne: RACGP; 2018 (updated 2023).
  8. 8. Hirsch JA, Singh V, Falco FJE, et al. Thoracic facet joint interventions. Pain Physician. 2016;19(4):E581–E593.
  9. 9. Erwin WM, Jackson PC. The costovertebral joint: anatomy, biomechanics, and clinical significance in thoracic back pain syndromes. J Can Chiropr Assoc. 2003;47(2):112–120.
  10. 10. Strayer RJ, Gunnerson JM, Brown LH, et al. Aortic dissection: clinical features, diagnosis, and management. Aust Crit Care. 2019;32(2):144–153.
  11. 11. Ombregt L. A system of orthopaedic medicine. 3rd edn. Edinburgh: Churchill Livingstone Elsevier; 2013. Chapter 18: Thoracic spine.
  12. 12. Lin CC, Chen KH, Li DM, et al. Characteristics and outcomes of patients presenting with thoracic back pain to the emergency department. Emerg Med Australas. 2020;32(5):805–811.
for PBS-listed medicines at participating pharmacies.
Cultural safety
Engagement with Aboriginal Community Controlled Health Organisations (ACCHOs) is essential. Cultural safety training for non-Indigenous clinicians, use of Aboriginal Health Workers and Liaison Officers, and incorporation of traditional healing practices alongside Western medicine improve treatment adherence and outcomes. Avoidance of eye contact, respect for gender-sensitive examination practices, and understanding of sorry business protocols are critical elements of culturally safe care.
Medication adherence
Complex DMARD regimens with frequent monitoring requirements present adherence challenges. Long-acting depot injections (e.g., methotrexate SC) may improve adherence compared to oral regimens. Community pharmacy partnerships through the Indigenous Pharmacy Programmes improve medication management.
Specific conditions
Rheumatic heart disease (RHD) requires secondary prophylaxis with benzathine penicillin G (BPG) 1.2 MU IM every 3–4 weeks for a minimum of 10 years or until age 21 (whichever is longer). RHD registers (e.g., NT RHD Register) facilitate recall and follow-up. The Australian RHD Endgame Strategy targets elimination by 2031.
Referral pathways
Referral through ACCHOs and Aboriginal Hospital Liaison Officers (AHLOs) improves engagement. The Specialist Outreach Assistance Programme provides funded specialist visits to remote communities. NT, WA, and QLD have specific rheumatology outreach programmes targeting Indigenous communities.

📚 References

  1. 1. Australian Institute of Health and Welfare (AIHW). Autoimmune disease in Australia. Cat. no. PHE 312. Canberra: AIHW; 2023.
  2. 2. Fraenkel L, Bathon JM, England BR, et al. 2021 American College of Rheumatology guideline for the treatment of rheumatoid arthritis. Arthritis Care Res. 2021;73(7):924–939.
  3. 3. Fanouriakis A, Kostopoulou M, Alber K, et al. 2019 update of the EULAR recommendations for the management of systemic lupus erythematosus. Ann Rheum Dis. 2019;78(6):736–745.
  4. 4. Chung SA, Langford CA, Maz M, et al. 2021 American College of Rheumatology/Vasculitis Foundation guideline for the management of antineutrophil cytoplasmic antibody-associated vasculitis. Arthritis Care Res. 2021;73(11):1583–1599.
  5. 5. Smolen JS, Landewé RBM, Bijlsma JWJ, et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2022 update. Ann Rheum Dis. 2023;82(1):3–18.
  6. 6. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook. Australian Government Department of Health; 2024. Available from: immunisationhandbook.health.gov.au.
  7. 7. Rheumatic Heart Disease Australia (RHDAustralia). The 2020 Australian guideline for prevention, diagnosis, and management of acute rheumatic fever and rheumatic heart disease. 3rd ed. Darwin: Menzies School of Health Research; 2020.
  8. 8. Pharmaceutical Benefits Scheme (PBS). PBS Schedule. Australian Government Department of Health. Available from: pbs.gov.au. Accessed 2024.
  9. 9. Agarwal S, Cunnington J, Nossent J. Autoimmune disease in Indigenous Australians: a systematic review. Int J Rheum Dis. 2021;24(12):1487–1498.
  10. 10. Pisetsky DS. Antinuclear antibody testing — misunderstood or misused? Clin Immunol. 2023;255:109717.
  11. 11. Bertsias GK, Tektonidou M, Amoura Z, et al. Joint European League Against Rheumatism and European Renal Association–European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. Ann Rheum Dis. 2012;71(11):1771–1782.
  12. 12. Ledingham J, Deighton C; British Society for Rheumatology Standards, Audit and Guidelines Working Group. Update on the British Society for Rheumatology guidelines for prescribing TNFα blockers in adults with rheumatoid arthritis. Rheumatology. 2005;44(2):155–158.
  13. 13. National Health and Medical Research Council (NHMRC). National statement on ethical conduct in human research. Canberra: NHMRC; 2023 (updated).
for PBS-listed medicines at participating pharmacies.
Cultural safety
Engagement with Aboriginal Community Controlled Health Organisations (ACCHOs) is essential. Cultural safety training for non-Indigenous clinicians, use of Aboriginal Health Workers and Liaison Officers, and incorporation of traditional healing practices alongside Western medicine improve treatment adherence and outcomes. Avoidance of eye contact, respect for gender-sensitive examination practices, and understanding of sorry business protocols are critical elements of culturally safe care.
Medication adherence
Complex DMARD regimens with frequent monitoring requirements present adherence challenges. Long-acting depot injections (e.g., methotrexate SC) may improve adherence compared to oral regimens. Community pharmacy partnerships through the Indigenous Pharmacy Programmes improve medication management.
Specific conditions
Rheumatic heart disease (RHD) requires secondary prophylaxis with benzathine penicillin G (BPG) 1.2 MU IM every 3–4 weeks for a minimum of 10 years or until age 21 (whichever is longer). RHD registers (e.g., NT RHD Register) facilitate recall and follow-up. The Australian RHD Endgame Strategy targets elimination by 2031.
Referral pathways
Referral through ACCHOs and Aboriginal Hospital Liaison Officers (AHLOs) improves engagement. The Specialist Outreach Assistance Programme provides funded specialist visits to remote communities. NT, WA, and QLD have specific rheumatology outreach programmes targeting Indigenous communities.

📚 References

  1. 1. Australian Institute of Health and Welfare (AIHW). Autoimmune disease in Australia. Cat. no. PHE 312. Canberra: AIHW; 2023.
  2. 2. Fraenkel L, Bathon JM, England BR, et al. 2021 American College of Rheumatology guideline for the treatment of rheumatoid arthritis. Arthritis Care Res. 2021;73(7):924–939.
  3. 3. Fanouriakis A, Kostopoulou M, Alber K, et al. 2019 update of the EULAR recommendations for the management of systemic lupus erythematosus. Ann Rheum Dis. 2019;78(6):736–745.
  4. 4. Chung SA, Langford CA, Maz M, et al. 2021 American College of Rheumatology/Vasculitis Foundation guideline for the management of antineutrophil cytoplasmic antibody-associated vasculitis. Arthritis Care Res. 2021;73(11):1583–1599.
  5. 5. Smolen JS, Landewé RBM, Bijlsma JWJ, et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2022 update. Ann Rheum Dis. 2023;82(1):3–18.
  6. 6. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook. Australian Government Department of Health; 2024. Available from: immunisationhandbook.health.gov.au.
  7. 7. Rheumatic Heart Disease Australia (RHDAustralia). The 2020 Australian guideline for prevention, diagnosis, and management of acute rheumatic fever and rheumatic heart disease. 3rd ed. Darwin: Menzies School of Health Research; 2020.
  8. 8. Pharmaceutical Benefits Scheme (PBS). PBS Schedule. Australian Government Department of Health. Available from: pbs.gov.au. Accessed 2024.
  9. 9. Agarwal S, Cunnington J, Nossent J. Autoimmune disease in Indigenous Australians: a systematic review. Int J Rheum Dis. 2021;24(12):1487–1498.
  10. 10. Pisetsky DS. Antinuclear antibody testing — misunderstood or misused? Clin Immunol. 2023;255:109717.
  11. 11. Bertsias GK, Tektonidou M, Amoura Z, et al. Joint European League Against Rheumatism and European Renal Association–European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. Ann Rheum Dis. 2012;71(11):1771–1782.
  12. 12. Ledingham J, Deighton C; British Society for Rheumatology Standards, Audit and Guidelines Working Group. Update on the British Society for Rheumatology guidelines for prescribing TNFα blockers in adults with rheumatoid arthritis. Rheumatology. 2005;44(2):155–158.
  13. 13. National Health and Medical Research Council (NHMRC). National statement on ethical conduct in human research. Canberra: NHMRC; 2023 (updated).