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Acute Pain: General Principles

Last updated 1 Jun 2026 ยท Pain & analgesia

๐Ÿ“‹ Key Information Summary

๐Ÿ“‹
  • Acute pain is a physiological warning signal lasting <3 months; effective management requires identifying the underlying cause, the pain mechanism (nociceptive vs neuropathic), and the degree of functional limitation.
  • Pain intensity assessment using validated tools (NRS 0โ€“10, BPS, FLACC in paediatrics) must be documented at every clinical encounter and guide stepwise escalation.
  • A multimodal analgesic approach combining pharmacological and non-pharmacological strategies is recommended as first-line for all acute pain presentations.
  • Simple analgesics โ€” paracetamol and/or an NSAID โ€” form the foundation of acute pain management; opioids are reserved for moderate-to-severe pain unresponsive to first-line agents.
  • Opioid prescribing should follow the lowest effective dose for the shortest duration; most acute pain requires โ‰ค3 days; post-surgical courses rarely exceed 7 days.
  • A tapering plan must be documented at the time of opioid initiation, with clear stop dates and arrangements for safe disposal of unused medication.
  • Nociceptive pain responds best to paracetamol, NSAIDs, and weak opioids; neuropathic pain may require adjuvant agents such as gabapentinoids, TCAs, or SNRIs.
  • Red flags โ€” progressive neurological deficit, cauda equina signs, septic features, suspected fracture or malignancy โ€” require urgent investigation and specialist referral before conservative analgesia.
  • Special populations (pregnancy, paediatrics, elderly, renal/hepatic impairment, opioid-dependent patients) require individualised dose adjustments and agent selection.
  • Aboriginal and Torres Strait Islander peoples experience higher rates of acute pain presentations; culturally safe communication, family involvement, and addressing barriers to access are essential components of care.
  • Regular review and reassessment of pain control, functional status, and adverse effects should occur within 48โ€“72 hours of any analgesic change.
  • Non-pharmacological strategies โ€” patient education, psychological support, physical therapy, heat/cold, and distraction โ€” should be offered concurrently with pharmacotherapy, not as an afterthought.

Introduction & Australian Epidemiology

Acute pain is defined as pain of recent onset (<3 months) that is associated with actual or potential tissue damage and serves as a physiological protective mechanism. Unlike chronic pain, acute pain typically resolves as the underlying pathology heals. Effective acute pain management is a core clinical competency across all medical, surgical, and emergency disciplines in Australian healthcare settings.

The Australian Institute of Health and Welfare (AIHW) reports that pain-related presentations account for a substantial proportion of emergency department (ED) attendances and general practice consultations nationally. The 2022 National Health Survey identified that approximately 3.2 million Australians experienced chronic pain, yet the burden of acute pain โ€” including post-surgical, post-traumatic, and acute musculoskeletal presentations โ€” remains under-quantified at a population level.

In Australia, acute pain management is guided by frameworks from Therapeutic Guidelines (eTG Analgesic), the Australian and New Zealand College of Anaesthetists (ANZCA) Acute Pain Management: Scientific Evidence, the Royal Australian College of General Practitioners (RACGP), and state-based Clinical Excellence Commissions. The Australian Commission on Safety and Quality in Health Care (ACSQHC) National Safety and Quality Health Service (NSQHS) Standards mandate that organisations have systems for pain assessment, management, and patient education.

โš ๏ธ
Key principle: Acute pain management depends on identifying the cause, characterising the pain type (nociceptive vs neuropathic), assessing intensity and functional impact, selecting appropriate multimodal interventions, and always planning for tapering and cessation.

This article establishes the general principles that underpin all acute pain management across clinical settings โ€” from the emergency department to general practice, post-operative wards, and community care. Specific acute pain conditions (e.g., renal colic, acute low back pain, acute migraine) are addressed in their respective guideline articles.

Cause of Pain

Identifying the underlying cause of acute pain is the first and most important step in management. The cause determines the diagnostic workup, the likely pain mechanism, the expected trajectory, and the most appropriate analgesic strategy. A structured approach classifies acute pain by mechanism, aetiology, and the presence of red flags requiring urgent intervention.

Pain Mechanisms

Mechanism Description Common Causes Analgesic Implications
Nociceptive โ€” Somatic Activation of peripheral nociceptors in skin, muscle, bone, or joint; well-localised, aching or sharp Fractures, lacerations, surgical incisions, osteoarthritis flares, muscle strains Responds well to paracetamol, NSAIDs, opioids; regional anaesthesia
Nociceptive โ€” Visceral Stimulation of visceral afferents from hollow organs or capsules; poorly localised, cramping or pressure-like Renal colic, biliary colic, appendicitis, bowel obstruction, dysmenorrhoea NSAIDs highly effective (smooth muscle relaxation); opioids for severe cases; antispasmodics
Neuropathic Nerve injury or dysfunction; burning, shooting, electric, tingling, allodynia Acute herpes zoster, radiculopathy, nerve compression, chemotherapy-induced peripheral neuropathy Poor response to simple analgesics; requires adjuvants (gabapentinoids, TCAs, SNRIs, lidocaine patches)
Inflammatory Release of inflammatory mediators (prostaglandins, cytokines, bradykinin) sensitising nociceptors Acute gout, post-operative inflammation, soft-tissue infections, inflammatory arthropathies NSAIDs and corticosteroids are highly effective; colchicine for gout; opioids as adjunct
Mixed / Central Sensitisation Peripheral injury with secondary central nervous system amplification Severe burns, polytrauma, prolonged untreated acute pain Aggressive multimodal approach; early ketamine consideration; gabapentinoid co-prescription

Common Acute Pain Aetiologies by Setting

Setting Common Causes
Emergency Department Musculoskeletal injury, renal colic, acute abdomen, fractures, burns, dental pain, headache (red flags excluded)
Post-Surgical Incisional/visceral pain, neuropathic component from nerve retraction, drain site pain, referred shoulder pain (diaphragmatic irritation)
General Practice Acute low back pain, neck pain, dental pain, post-injury pain, acute flare of osteoarthritis, herpes zoster
Inpatient Medical Acute pancreatitis, pleuritic chest pain, vaso-occlusive crises (sickle cell), procedural pain (central lines, drains)

Red Flags Requiring Urgent Investigation

๐Ÿšจ

Do not simply escalate analgesia if any red flag is present. Investigate the cause first.

  • Acute abdomen with peritonism โ€” consider surgical emergency
  • Back pain with progressive neurological deficit, saddle anaesthesia, or bladder/bowel dysfunction โ€” cauda equina syndrome
  • Chest pain with haemodynamic instability โ€” consider aortic dissection, pulmonary embolism, myocardial infarction
  • Severe headache with new neurological signs โ€” consider subarachnoid haemorrhage, meningitis, space-occupying lesion
  • Limb pain with absent pulses โ€” acute limb ischaemia
  • Pain with fever, rigors, and systemic toxicity โ€” septic arthritis, necrotising fasciitis, osteomyelitis
  • Suspected pathological fracture โ€” malignancy, osteoporosis

History and Examination Approach

A systematic pain history should address the mnemonic SOCRATES:

  • Site โ€” Where is the pain? Can the patient point to it with one finger?
  • Onset โ€” When did it start? Sudden vs gradual?
  • Character โ€” Sharp, dull, burning, cramping, throbbing?
  • Radiation โ€” Does it travel anywhere?
  • Associations โ€” Nausea, vomiting, fever, neurological symptoms?
  • Time course โ€” Constant or intermittent? Getting better or worse?
  • Exacerbating / relieving factors โ€” Movement, rest, position, medications?
  • Severity โ€” Numeric Rating Scale (NRS) 0โ€“10 at rest and with movement

Pain Intensity Assessment

Accurate, consistent, and documented pain intensity assessment is a NSQHS Standard requirement. Pain is a subjective experience; the patient's self-report is the gold standard. Assessment tools must be age-appropriate, cognitively accessible, and used consistently across all clinical encounters.

Validated Assessment Tools

Tool Population Description Scoring
Numeric Rating Scale (NRS) Adults and children โ‰ฅ8 years (cognitively intact) Patient rates pain from 0 (none) to 10 (worst imaginable) 0 = none; 1โ€“3 = mild; 4โ€“6 = moderate; 7โ€“10 = severe
Visual Analogue Scale (VAS) Adults (requires ability to use a 10 cm line) 100 mm horizontal line from "no pain" to "worst pain" 0โ€“30 mm = mild; 30โ€“54 mm = moderate; 55โ€“100 mm = severe
Verbal Rating Scale (VRS) Adults with cognitive or language barriers Categorical: none / mild / moderate / severe 4-point categorical scale
Wong-Baker FACES Children 3โ€“7 years; adults with cognitive impairment Six faces ranging from smiling to crying 0โ€“10 in increments of 2
FLACC Scale Infants 2 months to 7 years; non-verbal children Observational: Face, Legs, Activity, Cry, Consolability 0โ€“10 (each domain 0โ€“2)
BPS (Behavioural Pain Scale) Ventilated / sedated ICU adults Facial expression, upper limb movement, compliance with ventilation 3โ€“12; score >5 indicates significant pain
CPOT (Critical-Care Pain Observation Tool) Non-verbal ICU adults Facial expression, body movements, muscle rigidity, ventilator compliance / vocalisation 0โ€“8; score >3 indicates significant pain

Pain Intensity Categories and Treatment Escalation

Mild
NRS 1โ€“3 / VAS 1โ€“3 cm
Pain is present but does not interfere with function, sleep, or mood. Patient can perform activities of daily living (ADLs).
Setting: Outpatient / GP
Moderate
NRS 4โ€“6 / VAS 3.1โ€“5.4 cm
Pain interferes with some ADLs, concentration, or sleep. Patient is distressed but haemodynamically stable.
Setting: ED / Ward / GP with escalation
Severe
NRS 7โ€“10 / VAS 5.5โ€“10 cm
Pain dominates the clinical picture, prevents ADLs, may cause tachycardia and hypertension. Patient is highly distressed.
Setting: ED / Acute ward / Multidisciplinary input

Principles of Pain Assessment

  • Assess pain at rest and with movement (functional pain score) โ€” resting pain alone underestimates the clinical problem in post-operative and musculoskeletal presentations.
  • Reassess within 30โ€“60 minutes of parenteral analgesia and 60โ€“90 minutes of oral analgesia to determine treatment response.
  • Document the assessment tool used so that subsequent measurements are comparable.
  • In patients unable to self-report (dementia, delirium, intubation), use observational/behavioural tools (BPS, CPOT, Abbey Pain Scale) and look for physiological markers: tachycardia, hypertension, diaphoresis, grimacing.
  • Consider the 5th vital sign paradigm โ€” many Australian hospitals incorporate pain score into routine vital sign documentation, though this should not override clinical judgement.
  • Pain intensity alone does not dictate opioid use; consider the cause, mechanism, functional impact, and response to first-line agents before escalation.
โ„น๏ธ
Paediatric note: In pre-verbal children and neonates, observational tools (FLACC, N-PASS for neonates, r-FLACC for children with cognitive impairment) are essential. Always involve parents/carers in pain assessment โ€” they are often the most reliable observers of their child's comfort.

Multimodal Approach

Multimodal analgesia is the concurrent use of multiple analgesic agents and techniques that act by different mechanisms to achieve additive or synergistic pain relief. This approach reduces reliance on any single agent โ€” particularly opioids โ€” and thereby minimises dose-dependent adverse effects. It is endorsed by ANZCA, the ACSQHC, and international bodies including the WHO.

Stepwise Analgesic Ladder (Adapted for Australian Practice)

Step 1
Mild Pain (NRS 1โ€“3)
Paracetamol ยฑ NSAID. Non-pharmacological measures. Reassess in 24โ€“48 hours.
Step 2
Moderate Pain (NRS 4โ€“6)
Paracetamol + NSAID ยฑ weak opioid (codeine, tramadol). Add adjuvant if neuropathic features. Consider regional techniques.
Step 3
Severe Pain (NRS 7โ€“10)
Paracetamol + NSAID + strong opioid (morphine, oxycodone). Multimodal non-opioid agents continued. Specialist pain or anaesthetic input for refractory cases. Ketamine, nerve blocks, PCA as indicated.

Pharmacological Agents โ€” Overview

๐Ÿ’Š
Paracetamol
Panadolยฎ, Dymadonยฎ ยท Simple analgesic / antipyretic
Adult dose 500 mgโ€“1 g PO/IV QID (max 4 g/24 h; 2 g/24 h if <50 kg or hepatic impairment)
Paediatric dose 15 mg/kg PO/IV QID (max 60 mg/kg/24 h; 90 mg/kg/24 h under medical supervision inpatient)
Renal adjustment Caution in severe renal impairment (eGFR <30); extend interval to Q6โ€“8H; max 2 g/24 h
Key notes Cornerstone of multimodal analgesia. Safe in all trimesters of pregnancy. IV formulation available for post-operative and ED use (MBS item 2177). Hepatotoxicity risk at supratherapeutic doses.
PBS status โœ” PBS General Benefit (PO) ยท Authority Required (IV)
๐Ÿ’Š
Ibuprofen
Nurofenยฎ, Brufenยฎ ยท NSAID โ€” COX-1/COX-2 inhibitor
Adult dose 200โ€“400 mg PO TDS-QID (max 2.4 g/24 h for acute pain; 1.2 g/24 h OTC)
Paediatric dose 5โ€“10 mg/kg PO TDS (max 30 mg/kg/24 h; from 3 months of age)
Renal adjustment Avoid if eGFR <30 mL/min; use with caution if eGFR 30โ€“60; ensure adequate hydration
Key notes Avoid in third trimester of pregnancy (ductus arteriosus closure). GI protection (PPI) if >65 years or risk factors. Contraindicated in active GI bleeding, severe cardiac failure. Take with food.
PBS status โœ” PBS General Benefit
๐Ÿ’Š
Codeine
Panadeineยฎ (with paracetamol) ยท Weak opioid (prodrug)
Adult dose 30โ€“60 mg PO Q4โ€“6H PRN (max 240 mg/24 h)
Paediatric dose Not recommended <12 years (TGA 2015 restriction). 12โ€“18 years: 30โ€“60 mg Q4โ€“6H PRN with caution regarding CYP2D6 ultra-rapid metaboliser status.
Renal adjustment Reduce dose and extend interval in eGFR <30; active metabolites accumulate.
Key notes Variable metabolism via CYP2D6 โ€” ultra-rapid metabolisers at risk of toxicity; poor metabolisers have minimal analgesic effect. Most combined with paracetamol (ensure total paracetamol dose accounted for). Limited role in severe pain.
PBS status โœ” PBS General Benefit
๐Ÿ’Š
Tramadol
Tramalยฎ ยท Weak opioid + SNRI
Adult dose 50โ€“100 mg PO/IV Q4โ€“6H (max 400 mg/24 h)
Paediatric dose 1โ€“2 mg/kg PO/IV Q4โ€“6H (from 12 years for acute pain; limited data in younger children)
Renal adjustment Max 200 mg/24 h if eGFR <30; extend interval to Q12H.
Key notes Seizure risk (lowers threshold). Avoid with serotonergic medications (SSRIs, MAOIs) โ€” serotonin syndrome risk. Also subject to CYP2D6 variability. Often overused; evidence for superiority over paracetamol + NSAID is limited.
PBS status โœ” PBS General Benefit
๐Ÿ’Š
Morphine
MS Continยฎ, Ordineยฎ ยท Strong opioid โ€” gold standard
Adult dose Oral: 5โ€“10 mg Q4H PRN (opioid-naรฏve). IV: 2.5โ€“5 mg Q4H PRN or 1โ€“2 mg increments titrated. PCA: 1 mg bolus, 5 min lockout.
Paediatric dose Oral: 0.2โ€“0.3 mg/kg Q4H (max 0.5 mg/kg/dose). IV: 0.05โ€“0.1 mg/kg Q4H or 0.02 mg/kg/hr infusion.
Renal adjustment Active metabolite (M6G) accumulates โ€” reduce dose by 50% if eGFR <30; avoid repeated dosing in eGFR <15. Consider fentanyl or hydromorphone as alternatives.
Key notes First-line strong opioid in Australian hospitals. Tolerance develops within days. Common adverse effects: nausea/vomiting (prescribe antiemetic), constipation (prescribe stimulant laxative), sedation, respiratory depression. Naloxone should be available on ward. Prescribe for shortest effective duration.
PBS status โœ” PBS General Benefit (oral) ยท โœ” PBS General Benefit (injection)
๐Ÿ’Š
Oxycodone
Endoneยฎ, OxyNormยฎ ยท Strong opioid
Adult dose Oral: 5 mg Q4โ€“6H PRN (opioid-naรฏve). Modified-release: 10 mg Q12H (not for acute initiation).
Paediatric dose Oral: 0.1โ€“0.2 mg/kg Q4โ€“6H (limited data; specialist guidance recommended <12 years)
Renal adjustment Reduce dose and extend interval if eGFR <30; active metabolites (oxymorphone) may accumulate.
Key notes Oral bioavailability ~60โ€“87% (higher than morphine). Useful when morphine not tolerated. Same adverse effect profile as morphine. Modified-release formulations should NOT be used for acute pain initiation.
PBS status โœ” PBS General Benefit (immediate-release) ยท Authority Required (modified-release)
๐Ÿ’Š
Gabapentin
Neurontinยฎ ยท Gabapentinoid โ€” neuropathic pain adjuvant
Adult dose Start 300 mg PO OD at night, titrate to 300 mg TDS (max 3.6 g/24 h in divided doses)
Paediatric dose Limited data for acute pain; specialist guidance recommended
Renal adjustment eGFR 30โ€“59: max 600 mg BID; eGFR 15โ€“29: max 300 mg OD; eGFR <15: 300 mg alternate days
Key notes Effective in acute neuropathic pain (e.g., post-operative, herpes zoster). Post-operative gabapentinoid use may reduce opioid requirements. Dizziness and sedation are common. Use with caution in elderly (falls risk). Avoid abrupt cessation.
PBS status Authority Required (neuropathic pain)
๐Ÿ’Š
Ketamine (sub-anaesthetic)
Ketalarยฎ ยท NMDA receptor antagonist
Adult dose Sub-anaesthetic: 0.1โ€“0.3 mg/kg IV bolus or 0.1โ€“0.3 mg/kg/hr infusion. For procedural sedation: separate dosing protocols (not discussed here).
Paediatric dose Sub-anaesthetic infusion: 0.1โ€“0.3 mg/kg/hr IV; specialist supervision required.
Key notes Second-line for refractory acute pain, opioid-tolerant patients, opioid-induced hyperalgesia, and burns/procedural pain. Psychotomimetic effects (emergence reactions) โ€” co-administer midazolam 0.5โ€“1 mg IV to reduce. Monitor for hypertension, tachycardia. Specialist or senior clinician initiation recommended.
PBS status โœ” PBS General Benefit

Non-Pharmacological Strategies

Non-pharmacological interventions should be offered to all patients alongside medications, not as a replacement or afterthought:

  • Patient education: Explain the expected pain trajectory, the treatment plan, and the tapering strategy. Written information (e.g., PainAustralia resources) improves adherence.
  • Heat and cold: Ice/cold packs for acute musculoskeletal injury (first 48โ€“72 hours); heat for muscle spasm and chronic-type flares.
  • Physical therapy / early mobilisation: Reduces post-operative and musculoskeletal pain; prevents deconditioning. Refer to physiotherapy early.
  • Psychological support: Cognitive-behavioural techniques, relaxation, guided imagery. Anxiety amplifies pain perception.
  • Distraction and music therapy: Evidence supports use in paediatric and procedural pain contexts.
  • Transcutaneous electrical nerve stimulation (TENS): May provide adjunctive benefit in musculoskeletal and neuropathic pain. Limited PBS subsidy.
  • Positioning and splinting: Immobilisation of fractures/sprains, elevation of injured limbs, ergonomic support for back pain.

Regional and Interventional Techniques

When systemic analgesia is insufficient or causes intolerable adverse effects, regional anaesthetic techniques provide excellent site-specific analgesia:

  • Peripheral nerve blocks: Femoral nerve block for femoral fractures; interscalene block for shoulder surgery; wound infiltration (e.g., liposomal bupivacaine) for laparoscopic ports.
  • Epidural analgesia: Thoracic epidural for major abdominal/thoracic surgery โ€” superior dynamic pain relief; catheter-related complications (hypotension, urinary retention, rarely epidural haematoma/abscess).
  • Local anaesthetic wound infiltration: Simple, low-risk, can be performed by surgeons intra-operatively.
  • IV regional anaesthesia (Bier block): Short procedures on the distal limb.
โœ…
Best practice: Combine regular paracetamol + scheduled NSAID (if not contraindicated) + as-needed opioid (short-acting) + adjuvant agent if neuropathic component + non-pharmacological measures. This is the foundation of Australian acute pain management at every level of care.

Tapering Plan

Every prescription of opioid analgesia for acute pain must include a documented tapering and cessation plan. The goal of acute pain management is to treat the pain until the underlying cause resolves, not to create a new chronic problem of opioid dependence. The Australian Institute of Health and Welfare (AIHW) and the Therapeutic Goods Administration (TGA) have emphasised the importance of short-course prescribing and proactive deprescribing.

Core Principles of Tapering

  • Plan the exit at the point of entry: When initiating an opioid, communicate the expected duration and the stop date to the patient. Document this in the clinical notes and on the discharge prescription.
  • Duration benchmarks:
    • Most acute non-surgical pain (renal colic, musculoskeletal injury): โ‰ค3 days of opioid
    • Minor surgery (laparoscopic, dental): โ‰ค3โ€“5 days
    • Major surgery (open abdominal, orthopaedic): โ‰ค5โ€“7 days; rarely >14 days
    • If opioids required beyond 2 weeks for an "acute" condition, reassess the diagnosis and consider specialist input
  • Tapering is not abrupt cessation in patients who have received opioids for >7 days. Reduce the total daily dose by 10โ€“25% every 1โ€“3 days until cessation.
  • Patients on opioids for โ‰ค5 days may usually stop without tapering, provided no features of physiological dependence have developed.

Stepwise Tapering Approach

Step 1
Assess Current Use
Review total daily opioid dose (regular + PRN), duration of use, reported pain scores, functional status, and any signs of dependence (craving, escalating PRN use, requesting early repeats).
Step 2
Optimise Non-Opioid Analgesia
Ensure regular paracetamol and NSAID (if appropriate) are being used at full therapeutic doses before reducing opioids. Add neuropathic adjuvant if indicated.
Step 3
Reduce PRN Opioid First
Discontinue PRN opioid doses before reducing regular doses. Educate patients that PRN doses are the first to stop as pain improves.
Step 4
Taper Regular Doses
Reduce total daily dose by 10โ€“25% every 1โ€“3 days. Convert to a single long-acting formulation if still requiring scheduled dosing, then taper that formulation. In practice: if on oxycodone 5 mg QID, reduce to 5 mg TDS โ†’ 5 mg BD โ†’ 5 mg nocte โ†’ cease.
Step 5
Cease and Review
Stop opioids completely. Schedule a review within 1โ€“2 weeks to confirm pain resolution and absence of withdrawal symptoms. Dispose of unused opioids โ€” encourage return to community pharmacy (National Return and Disposal of Unwanted Medicines โ€” RUM Project).

Tapering Schedule โ€” Practical Example

Day Oxycodone (oral) Paracetamol NSAID Notes
Day 1โ€“3 5 mg QID PRN (max 20 mg/day) 1 g QID scheduled Ibuprofen 400 mg TDS Acute phase; record PRN usage
Day 4โ€“5 5 mg TDS PRN (reduce max to 15 mg/day) 1 g QID scheduled Continue Expected trajectory: decreasing opioid need
Day 6โ€“7 5 mg BD PRN (if still needed) 1 g QID scheduled Step down to PRN Most patients able to cease opioid
Day 8+ Cease 1 g TDSโ€“QID PRN PRN Review at 1โ€“2 weeks; physiotherapy referral

When to Seek Specialist Input

โš ๏ธ
  • Opioid requirement beyond 2 weeks for an acute condition โ€” consult acute pain service or pain medicine specialist
  • Signs of opioid dependence (tolerance, withdrawal symptoms, loss of control, escalating doses) โ€” refer to addiction medicine or drug and alcohol service
  • Complex pain syndromes with mixed nociceptive/neuropathic features โ€” refer to pain medicine specialist
  • Patients on long-term opioid therapy for chronic pain who present with new acute pain โ€” consult with their usual prescriber; do not abruptly change chronic regimen

Safe Opioid Disposal

  • Advise patients to return unused opioids to any community pharmacy for safe destruction (RUM Project โ€” National Return and Disposal of Unwanted Medicines Ltd).
  • Do not flush opioids down the toilet or place in general waste.
  • Provide written information on safe storage (locked, out of reach of children and visitors) during the treatment course.
  • Document the conversation about safe storage and disposal in the discharge summary and GP letter.

Special Populations

๐Ÿคฐ

Pregnancy

Paracetamol โ€” First-line; safe in all trimesters at standard doses.
Ibuprofen / NSAIDs โ€” Contraindicated from 30 weeks gestation (premature ductus arteriosus closure, oligohydramnios). Avoid in first trimester if possible (miscarriage association). Use with caution 13โ€“29 weeks only if benefits outweigh risks.
Codeine โ€” Use with caution; crosses placenta. Associated with neonatal respiratory depression at high doses. Avoid prolonged use.
Morphine / Oxycodone โ€” Use lowest effective dose for shortest duration. Neonatal withdrawal syndrome risk with prolonged maternal use. Short courses (<5 days) generally acceptable.
Tramadol โ€” Avoid; limited safety data in pregnancy; risk of neonatal seizures.
Gabapentin โ€” Avoid unless benefit clearly outweighs risk; limited human data; animal studies show developmental toxicity.
Multimodal non-pharmacological approaches (TENS, heat, physiotherapy, hydrotherapy) are preferred adjuncts in pregnancy.
๐Ÿ‘ถ

Paediatrics

Paracetamol โ€” 15 mg/kg PO/IV Q4โ€“6H (max 60 mg/kg/24 h). First-line from neonatal period. Weight-based dosing essential.
Ibuprofen โ€” 5โ€“10 mg/kg PO TDS from 3 months. Avoid in dehydrated children. Short courses only.
Codeine โ€” Contraindicated <12 years (TGA restriction, 2015). Contraindicated 12โ€“18 years post-tonsillectomy/adenoidectomy. CYP2D6 variability risk.
Morphine โ€” 0.2โ€“0.3 mg/kg PO Q4H; 0.05โ€“0.1 mg/kg IV Q4H. Use for moderate-to-severe pain only. Continuous SpOโ‚‚ monitoring for IV use. PCA from ~7 years (with appropriate supervision).
Ketamine (sub-dissociative) โ€” Procedural and refractory pain. Must be administered by experienced clinician with monitoring. 0.1โ€“0.3 mg/kg IV for analgesic dosing.
Use FLACC, Wong-Baker FACES, or age-appropriate NRS for pain assessment. Involve parents/carers. Non-pharmacological measures (distraction, comfort positioning, breastfeeding for neonates) are first-line adjuncts.
๐Ÿ‘ด

Elderly (โ‰ฅ65 years)

Paracetamol โ€” First-line. Max 3 g/24 h (reduced from 4 g). Monitor hepatic function.
NSAIDs โ€” Avoid if possible; increased GI bleeding, renal impairment, cardiovascular risk, falls. If essential: use lowest dose for shortest duration + PPI cover.
Opioids โ€” "Start low, go slow." Reduce initial morphine/oxycodone dose by 50% (e.g., morphine 2.5 mg IV, oxycodone 2.5 mg PO). Increased risk of: falls, constipation, confusion/delirium, respiratory depression, urinary retention. Prescribe regular laxatives (docusate + sennosides). Naloxone plan on ward.
Gabapentinoids โ€” Reduce dose significantly. High falls risk with dizziness and sedation. Start gabapentin 100 mg nocte, titrate slowly.
Elderly patients often under-report pain due to stoicism, fear of diagnosis, or cognitive impairment. Use observational tools if self-report unreliable. Screen for delirium as both a cause and complication of uncontrolled pain.
๐Ÿซ˜

Renal Impairment

Paracetamol โ€” Safe to use; reduce max to 2 g/24 h in severe impairment (eGFR <15). Extend interval.
NSAIDs โ€” Avoid in eGFR <30. Risk of acute kidney injury, fluid retention, hyperkalaemia. In eGFR 30โ€“60: short courses with monitoring only.
Morphine โ€” Avoid in eGFR <15 (active metabolite M6G accumulation โ†’ prolonged sedation, respiratory depression). If eGFR 15โ€“30: reduce dose by 50%, monitor closely.
Oxycodone โ€” Reduce dose by 25โ€“50% if eGFR <30; metabolites still accumulate but less than morphine.
Fentanyl โ€” Preferred strong opioid in severe renal impairment (inactive metabolites). No renal dose adjustment required.
Gabapentin โ€” Dose adjustment required (see drug card above).
Dialysis: morphine and codeine are significantly cleared by haemodialysis but may cause rebound pain. Fentanyl is not dialysed. Consult renal and pharmacy teams.
๐Ÿซ

Hepatic Impairment

Paracetamol โ€” Max 2 g/24 h in significant liver disease (Child-Pugh B/C). Risk of hepatotoxicity at lower thresholds.
NSAIDs โ€” Avoid in severe hepatic impairment; coagulopathy, variceal bleeding, fluid retention. Hepatotoxicity risk (especially diclofenac).
Opioids โ€” Reduce doses by 50% in moderate impairment; avoid morphine and codeine in severe liver disease (prolonged half-life, increased bioavailability). Fentanyl or hydromorphone may be preferred with caution.
Tramadol โ€” Avoid in severe hepatic impairment (prolonged elimination, seizure risk).
Coagulopathy (elevated INR) increases procedural bleeding risk. Avoid intramuscular injections. Monitor for hepatic encephalopathy precipitated by opioids (constipation, sedation).
๐Ÿ›ก๏ธ

Opioid-Tolerant / Chronic Pain Patients

Principle โ€” Patients on long-term opioids for chronic pain who present with acute pain require higher doses to achieve analgesia (tolerance). Do not prescribe their usual chronic dose โ€” add to it for acute-on-chronic pain.
Calculation โ€” Calculate the total daily opioid dose (24-hour morphine equivalent), then add 50โ€“100% for acute pain management. Use short-acting formulations for acute escalation.
Ketamine โ€” Particularly useful in opioid-tolerant patients; NMDA receptor antagonism counteracts opioid tolerance and hyperalgesia.
Consult โ€” Involve acute pain service, pain medicine specialist, and/or the patient's usual prescriber. Do not abruptly reduce or cease their chronic opioid regimen.
Patients on buprenorphine (Suboxoneยฎ, Subutexยฎ) for opioid dependence require specific management โ€” consult addiction medicine. Buprenorphine's high receptor affinity may block other opioids; options include continuing buprenorphine + multimodal approach, or supervised dose modification.
Aboriginal and Torres Strait Islander Health Considerations

Aboriginal and Torres Strait Islander peoples experience a significantly higher burden of acute pain presentations compared to non-Indigenous Australians, driven by higher rates of injury, musculoskeletal conditions, dental disease, renal calculi, and post-surgical complications. The AIHW reports that Indigenous Australians are hospitalised for injuries at approximately twice the rate of non-Indigenous Australians. Pain management must be culturally safe, family-centred, and responsive to the unique barriers experienced by First Nations peoples across urban, regional, and remote settings.

Cultural Safety
Use culturally appropriate pain assessment tools and communication approaches. Understand that pain expression varies across cultures โ€” stoicism does not mean absence of pain. Involve Aboriginal and Torres Strait Islander Health Workers and Liaison Officers (AHWLOs) in pain assessment and management planning. Respect cultural obligations (e.g., sorry business, kinship responsibilities) that may affect hospital attendance and follow-up.
Language and Communication
Use interpreter services when English is not the primary language (e.g., Aboriginal Interpreter Service in NT, YATI in SA). Avoid medical jargon. Use visual pain scales (Wong-Baker FACES) across age groups where literacy may be a barrier. Explain the tapering plan in clear, plain language and provide written take-home information.
Remote and Rural Access
Many Aboriginal and Torres Strait Islander peoples live in remote communities where specialist pain services, pharmacies, and imaging are limited. Primary Health Care nurses and Remote Area Aboriginal Health Practitioners often manage acute pain as first-line clinicians. Ensure access to essential analgesics (paracetamol, ibuprofen, codeine, morphine) through Remote Area Aboriginal Health Practitioner (RAAHP) supply schedules and Section 100/Remote Area Aboriginal Health Services supply. Telehealth pain medicine consultations should be utilised for complex cases.
Medication Safety and Storage
Overcrowded housing and communal living arrangements increase the risk of medication diversion and accidental paediatric opioid ingestion. Provide opioids in limited quantities (3โ€“5 days at a time). Counsel on safe storage in locked containers. Encourage return of unused medications to clinic or health service. Community-controlled health organisations may implement medication management programs (e.g., QUMAX, Mewan).
Multimodal and Integrative Approaches
Support integration of culturally valued healing practices alongside Western analgesia where appropriate โ€” this may include traditional healing, bush medicine, and social and emotional wellbeing frameworks. Physiotherapy and exercise-based programs adapted for community settings can be highly effective for musculoskeletal pain. PainAustralia and NACCHO resources can support community-based pain education.
Opioid Stewardship
Indigenous Australians are disproportionately affected by opioid-related harm, including opioid dependence and opioid-related deaths. Prescribe the lowest effective dose for the shortest duration. Taper and cease promptly. Ensure follow-up is arranged through the local Aboriginal Community Controlled Health Service (ACCHS). Be aware of the real risk of codeine and tramadol dependence in communities where these have historically been over-prescribed.
๐Ÿ“‹
Key resource: The RACGP's National Guide to a Preventive Health Assessment for Aboriginal and Torres Strait Islander People (3rd edition) and the AIHW Aboriginal and Torres Strait Islander Health Performance Framework provide frameworks for addressing pain and injury in the context of broader health and social determinants. RHDAustralia guidelines address rheumatic fever-related pain, which disproportionately affects Indigenous children in northern and central Australia.

๐Ÿ“š References

  1. 1. Australian and New Zealand College of Anaesthetists (ANZCA), Faculty of Pain Medicine. Acute Pain Management: Scientific Evidence. 5th ed. Melbourne: ANZCA; 2020.
  2. 2. Australian Commission on Safety and Quality in Health Care (ACSQHC). National Safety and Quality Health Service Standards. 2nd ed. Sydney: ACSQHC; 2021.
  3. 3. Australian Institute of Health and Welfare (AIHW). Pain in Australia. Cat. no. PHE 253. Canberra: AIHW; 2020.
  4. 4. Schug SA, Palmer GM, Scott DA, Halliwell R, Trinca J. Acute pain management: scientific evidence, fourth edition, 2015. Anaesthesia and Intensive Care. 2015;43(1):1โ€“90.
  5. 5. Royal Australian College of General Practitioners (RACGP). Prescribing drugs of dependence in general practice, Part B: Benzodiazepines, opioids and other drugs. Melbourne: RACGP; 2015 (updated 2022).
  6. 6. World Health Organization (WHO). WHO Guidelines on the Pharmacological Treatment of Persisting Pain in Children with Medical Illnesses. Geneva: WHO; 2012.
  7. 7. Therapeutic Goods Administration (TGA). Codeine information hub โ€” regulatory changes. Canberra: Department of Health and Aged Care; 2018. Available from: https://www.tga.gov.au/news-events/media-release/changes-codeine-access.
  8. 8. Dowell D, Ragan KR, Jones CM, Baldwin GT, Chou R. CDC Clinical Practice Guideline for Prescribing Opioids for Pain โ€” United States, 2022. MMWR Recomm Rep. 2022;71(No. RR-3):1โ€“95.
  9. 9. Australian Institute of Health and Welfare (AIHW). Aboriginal and Torres Strait Islander Health Performance Framework: Summary report 2023. Canberra: AIHW; 2023.
  10. 10. PainAustralia. National Pain Strategy. Sydney: PainAustralia; 2019. Available from: https://www.painaustralia.org.au.
  11. 11. Chou R, Gordon DB, de Leon-Casasola OA, et al. Management of postoperative pain: a clinical practice guideline from the American Pain Society, the American Society of Regional Anesthesia and Pain Medicine, and the American Society of Anesthesiologists' Committee on Regional Anesthesia. J Pain. 2016;17(2):131โ€“157.
  12. 12. Royal Australian College of General Practitioners (RACGP). National Guide to a Preventive Health Assessment for Aboriginal and Torres Strait Islander People. 3rd ed. Melbourne: RACGP; 2018.
  13. 13. National Return and Disposal of Unwanted Medicines (NatRUM). The RUM Project: safe disposal of unwanted medicines. Available from: https://www.returnmed.com.au.
  14. 14. Macintyre PE, Schug SA, Scott DA, Visser EJ, Walker SM; APM:SE Working Group. Acute Pain Management: Scientific Evidence. 5th ed. Melbourne: ANZCA Faculty of Pain Medicine; 2020.
  15. 15. Gaskell H, Derry S, Moore RA, McQuay HJ. Single dose oral oxycodone and oxycodone plus paracetamol (acetaminophen) for acute postoperative pain in adults. Cochrane Database Syst Rev. 2009;(3):CD002763.
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 ยฑ NSAID; manual therapy
2โ€“6 weeks
Provocable on palpation; no red flags
Thoracic compression fracture
Paracetamol; ยฑ calcitonin; DXA + osteoporosis Rx
6โ€“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 ยฑ morphine; lap cholecystectomy
Surgical within 72 h (cholecystitis)
RUQ/infrascapular; post-prandial; RUQ US

๐Ÿ“š 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):760โ€“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):60โ€“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):395โ€“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):E581โ€“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):112โ€“120.
  10. 10. Strayer RJ, Gunnerson JM, Brown LH, et al. Aortic dissection: clinical features, diagnosis, and management. Aust Crit Care. 2019;32(2):144โ€“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):805โ€“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 3โ€“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.

๐Ÿ“š 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):924โ€“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):736โ€“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):1583โ€“1599.
  5. 5. Smolen JS, Landewรฉ 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):3โ€“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):1487โ€“1498.
  10. 10. Pisetsky DS. Antinuclear antibody testing โ€” 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 Associationโ€“European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. Ann Rheum Dis. 2012;71(11):1771โ€“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 TNFฮฑ blockers in adults with rheumatoid arthritis. Rheumatology. 2005;44(2):155โ€“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 3โ€“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.

๐Ÿ“š 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):924โ€“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):736โ€“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):1583โ€“1599.
  5. 5. Smolen JS, Landewรฉ 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):3โ€“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):1487โ€“1498.
  10. 10. Pisetsky DS. Antinuclear antibody testing โ€” 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 Associationโ€“European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. Ann Rheum Dis. 2012;71(11):1771โ€“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 TNFฮฑ blockers in adults with rheumatoid arthritis. Rheumatology. 2005;44(2):155โ€“158.
  13. 13. National Health and Medical Research Council (NHMRC). National statement on ethical conduct in human research. Canberra: NHMRC; 2023 (updated).