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Opioid Analgesic — Strong Pregnancy: Should be avoided in pregnant or lactating patients. Data in pregnancy are limited; animal studies have not shown relevant reproductive toxicity. Prolonged use during pregnancy may cause neonatal withdrawal symptoms, and administration during labour may cause neonatal respiratory depression — make a careful risk/benefit assessment before use, and closely monitor neonates born to mothers treated in the last 3 to 4 weeks of pregnancy. Breast-feeding: oxycodone is excreted in human milk (milk:plasma ratio 3.4:1) and may cause respiratory depression in the breastfed infant — should not be used in breast-feeding mothers.

Oxycodone (Orthopaedic Post-operative Pain)

Brand names: OxyContin, OxyNorm, Lynlor

Oxycodone is a strong opioid analgesic used for moderate-to-severe acute pain after orthopaedic surgery, available in immediate- and modified-release oral and parenteral forms.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Opioid-naïve adults (over 18 years): starting dose 5 mg, then titrate individually
Route: Oral
Frequency: Every 6 hours
ROUTE CAVEAT: the fetched UK SPC is Oxycodone Hydrochloride 1 mg/ml oral solution, so this source gives ORAL dosing only; no parenteral oxycodone regimen is included. Opioids should be individually dose titrated because of large inter-patient differences in pharmacokinetics, pain intensity, pain origin, possible tolerance and age. A higher initial dose may be required for pain control depending on the patient's need; if the pain responds to opioid, the dose may be increased daily until the required effect is achieved or unacceptable side effects occur. Patients already receiving opioids may start at a higher dose depending on previous experience. CONVERSIONS stated in the SPC: 5 mg oral oxycodone is equivalent to 10 mg oral morphine (at initiation it may be advisable to use a lower dose than the equivalent dose); 2 mg oral oxycodone is equivalent to 1 mg parenteral oxycodone. For breakthrough pain in patients on a prolonged-release oxycodone formulation, give 1/8 to 1/6 of the prolonged-release daily dose. After starting, check regularly for pain relief and opioid adverse effects and adjust the dose for the most effective pain control with minimal adverse effects. Oxycodone should not be used longer than necessary; agree treatment duration, goals and an end-of-treatment plan before starting, and taper gradually to prevent withdrawal. Elderly: exercise caution — plasma concentrations appear higher than in younger adults — but a dose adjustment is not usually necessary. No adult maximum daily dose is stated in this SPC. PAEDIATRIC: opioids must only be used for appropriate indications and prescribed by a specialist experienced in managing severe pain in children; the SPC gives a regimen for adolescents from 12 years and states oxycodone is not recommended below 12 years (safety and efficacy not established, no data). Verify any paediatric dose against a children's formulary. Source quote (§4.2): 'The starting dose for opioid naïve patients is 5 mg every 6 hours, but a higher initial dose may be required for pain control, depending on the patient's need.'

Dose adjustments

Renal

Oxycodone plasma concentrations are higher in renal impairment. Dose initiation should be conservative: the recommended adult starting dose should be reduced by 50% (for example a total daily dose of 10 mg orally in opioid-naïve patients), with each patient then titrated to adequate pain control. (The same 50% starting-dose reduction applies in hepatic impairment.)

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substance or to any of the excipients
  • Severe chronic obstructive pulmonary disease
  • Cor pulmonale
  • Severe bronchial asthma
  • Severe respiratory depression with hypoxia and/or hypercapnia
  • Paralytic ileus

Side effects

  • Nausea and constipation — the most commonly reported reactions, each in approximately 25 to 30% of patients
  • Vomiting (nausea and vomiting are usually temporary and may be treated with an antiemetic; constipation should be treated with appropriate laxatives)
  • Respiratory depression — the most serious reaction, most likely in elderly, debilitated or opioid-naïve patients
  • Somnolence, dizziness, headache (common); tremor, lethargy, amnesia (uncommon)
  • Anxiety, depression, insomnia, nervousness, changes in cognitive performance including abnormal thinking and confusion (common); drug dependence (uncommon)
  • Decreased appetite (common); hypersensitivity (common), anaphylactic/anaphylactoid reaction (frequency not known)

Interactions

  • CYP3A4 inhibitors — increase oxycodone plasma concentration, producing increased or prolonged opioid effects; more pronounced with combined CYP2D6 and CYP3A4 inhibition. If concomitant use is necessary consider reducing the oxycodone dose and monitor frequently for respiratory depression and sedation (US label §7)
  • Stopping a CYP3A4 inhibitor lowers oxycodone concentrations, risking loss of efficacy or a withdrawal syndrome in physically dependent patients; consider increasing the oxycodone dose (US label §7)

Clinical monograph

How it works

It is a mu-opioid receptor agonist (with some kappa activity) that reduces central pain transmission and perception.

Prescribing in practice

  • Observe for respiratory depression and excessive sedation, especially when combined with other CNS depressants or in opioid-naive patients after surgery.
  • Reduce dose in hepatic and renal impairment and in the elderly, where clearance is reduced.
  • Use a clear stop or review plan with laxative and antiemetic cover to avoid prolonged post-operative opioid use.

Monitoring

Monitor pain, sedation and respiratory rate, and review the ongoing need as acute post-operative pain settles.

Counselling the patient

  • May cause drowsiness; avoid driving or operating machinery if affected.
  • Take regular laxatives to prevent constipation.
  • Do not combine with alcohol or other sedating medicines.

Evidence & guidelines

UK perioperative pain guidance supports short-course strong opioids within multimodal analgesia, minimising dose and duration after orthopaedic surgery.

Reference: MHRA DSU 2017 (Gabapentinoids); ERAS Orthopaedic Protocols; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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