Chronic Non-Cancer Pain & Opioid Stewardship

Chronic non-cancer pain (CNCP) is pain lasting beyond three months that is not due to cancer or its treatment. Opioids have only a selective place in its management — guidelines increasingly restrict them to patients whose pain and function have not responded to other therapies.

Assessment

Use a biopsychosocial framework: pain history and mechanism, prior treatment response, functional impact, and psychological/social contributors (mood, sleep, catastrophising, work and relationship stress). A relevant musculoskeletal or neurological examination is important, and screening tools exist for the psychosocial contributors.

Before considering opioids, review the patient’s history of substance use disorder (SUD), concurrent psychiatric, pulmonary, renal or hepatic disease, and concurrent medications (especially benzodiazepines).

Non-opioid management

Optimise non-drug and non-opioid therapies as the primary intervention before any opioid trial — exercise and activity-based interventions, psychological therapies (CBT), and multidisciplinary care where available. Multidisciplinary biopsychosocial rehabilitation, combining GP, physiotherapy and psychology input, is more consistently effective than any single modality, though the ideal composition of a multidisciplinary team isn’t established by evidence.

Non-opioid drug options — paracetamol, NSAIDs, and (for neuropathic pain) tricyclic antidepressants or gabapentinoids — should be tried and optimised before, and continued alongside, any opioid.

Opioid trial

Reserve opioids for moderate-to-severe pain that significantly affects function or quality of life and has not responded to other therapies. Before starting:

• Discuss known risks and realistic benefits, and the patient’s own responsibilities for managing therapy (including risks from unintentional or intentional sharing).
• Establish treatment goals for pain and function, and agree in advance how therapy will be stopped if it doesn’t work — an “exit strategy.”
• Consider a urine drug test (UDT) before starting, to check for prescribed medications as well as other controlled or illicit drugs.
• Consider having only one prescriber for ongoing analgesics, and share care with a pain specialist for higher-risk patients.

Starting an opioid. Unless contraindicated, prefer an opioid with lower harm potential — oral tapentadol, transdermal buprenorphine or oral tramadol. Start low and increase gradually, monitoring effectiveness with the 5As (below) and a validated pain/function tool such as PEG (Pain, Enjoyment, General activity). A favourable response is usually apparent within 2–4 weeks; run the trial over 8–12 weeks to allow for normal variation, and don’t continue if there’s no clinically meaningful benefit by three months.

Dose ceiling. Reassess carefully before increasing beyond 50 mg oral morphine equivalent (OME) per day. A ceiling of 100 mg OME/day is recommended for Australian general practice — above this, seek specialist review.

Monitoring

Review benefit and harm within 1–4 weeks of starting or of any dose escalation, then at least every 3 months. Continue only if there is clinically meaningful improvement in pain and function that outweighs the risks. Structure each review around the 5As:

• Activity — change in function (sitting/standing/walking tolerance, activities of daily living).
• Analgesia — pain scores (average and worst, 0–10) and % relief from medication.
• Affect — mood and sleep.
• Adverse effects — constipation, nausea, dizziness, drowsiness.
• Aberrant behaviours — taking medication as prescribed, unsanctioned dose escalation, lost scripts or requests for early repeats.

Consider a UDT at initiation and at least annually thereafter, using clinical discretion rather than testing everyone — UDTs and treatment agreements haven’t been shown to reduce overall rates of misuse or overdose, but they clarify expectations and have an educational role.

Regulatory requirements

Opioids are Schedule 8 (S8) medicines. In most states, a patient prescribed an S8 opioid for two months or longer needs state regulatory authority; in NSW, only buprenorphine, hydromorphone and methadone require an authority among the oral opioids. PBS rules also require an independent prescribing review at 12 months of continuous therapy — use a structured checklist for this. Check the current real-time prescription monitoring system before prescribing, and contact the Prescription Shopping Information Service if diversion or doctor-shopping is suspected.

Naloxone

Offer take-home naloxone when overdose-risk factors are present — dose ≥50 mg OME/day, concurrent benzodiazepine use, or a history of overdose or substance use disorder. Naloxone is available as an S4 PBS-subsidised injection or over-the-counter as an S3 from a pharmacy, and can be supplied to a family member or co-resident to protect against unintentional overdose (e.g. of a child in the household).

Tapering

See Deprescribing & Polypharmacy for the general principles of safe tapering that apply here too.

Taper and discontinue opioids when there’s no functional improvement, the trial’s agreed goals aren’t met, or aberrant behaviours appear — never stop abruptly without a plan; doing so without a feasible tapering offer can be considered a failure of duty of care.

Where there’s no evidence of a substance use disorder:

• After a short trial that failed its goals: a faster taper is reasonable — stepwise reduction of 10–25% of the starting dose each week.
• For longer-term use: reduce by 10% of the original dose every 5–7 days until 30% of the original dose remains, then by 10% of the remaining dose weekly. This pattern rarely precipitates withdrawal and supports adherence.
• Slow the pace (larger gaps between reductions, e.g. 2–3 months) if a previous attempt failed or comorbidities complicate the taper.

Withdrawal symptoms (nausea, diarrhoea, muscle pain, myoclonus) can be managed with clonidine 0.1–0.2 mg orally every 6 hours or supportive care — don’t treat withdrawal with further opioids or benzodiazepines. Mild symptoms can persist for up to 6 months after cessation.

Iatrogenic dependence. Some patients on long-term high-dose opioids for CNCP represent de facto opioid dependence. Tapering should be attempted in anyone on >100 mg OME/day. If it becomes apparent during weaning that the primary problem is opioid use disorder rather than pain, offer or arrange medication-assisted treatment (buprenorphine-naloxone or methadone) and refer to an addiction specialist — see the separate page on opioid dependence and withdrawal for that pathway.

Referral

• Pain requiring escalation beyond 100 mg OME/day, or an opioid trial not achieving its goals.
• Suspected opioid use disorder — refer to an addiction specialist; medication-assisted treatment (methadone/buprenorphine) needs a state-approved prescriber.
• Complex psychiatric comorbidity, high-risk aberrant behaviour, or an unsuccessful taper — involve a pain clinic or drug and alcohol service. Every state and territory runs a 24-hour alcohol and drug advisory service for urgent prescriber advice.
• Suspected complex regional pain syndrome or another condition needing specialist pain-medicine input.

Safety-netting

Warn patients starting or escalating opioids about sedation, respiratory depression risk (especially with concurrent benzodiazepines or alcohol), constipation, and the driving implications of a new or increased dose. Confirm they know how to recognise and respond to an overdose if naloxone has been supplied, and that ongoing supply depends on regular review, not automatic repeats.