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Opioid Analgesic — Strong Pregnancy: Use with caution — neonatal opioid withdrawal syndrome; avoid near term

Oxycodone (Orthopaedic Post-operative Pain)

Brand names: OxyContin, OxyNorm, Lynlor

Adult dose

Dose: Oral IR: 5–10 mg every 4–6 hours; Oral SR: 10–20 mg every 12 hours
Route: Oral (or IV in hospital setting)
Frequency: Every 4–6 hours (IR) or every 12 hours (SR)
Max: No ceiling dose — titrate to pain; typical post-arthroplasty 20–40 mg/day total
Similar efficacy to morphine but with higher oral bioavailability (~60–87% vs morphine 30–40%). Better tolerated in patients with nausea on morphine. Available as oral liquid for patients who cannot swallow tablets. Always prescribe laxative. Convert IR to SR when pain is controlled.

Paediatric dose

Dose: 0.05–0.1 mg/kg
Route: Oral
Frequency: Every 4–6 hours
Max: 5 mg per dose
Paediatric post-operative pain — under specialist guidance; limited evidence for IR oxycodone vs other opioids in children

Dose adjustments

Renal

Advantage over morphine in renal impairment — oxycodone metabolites are less active than morphine-6-glucuronide; reduce dose frequency in severe renal impairment

Hepatic

Reduce dose in hepatic impairment — increased bioavailability due to reduced first-pass

Paediatric weight-based calculator

Paediatric post-operative pain — under specialist guidance; limited evidence for IR oxycodone vs other opioids in children

Clinical pearls

  • Opioid equivalence: oral oxycodone 10 mg ≡ oral morphine 15 mg (ratio 1:1.5) — important for opioid rotation or when prescribing background SR analgesia
  • Renal impairment advantage: oxycodone metabolites (oxymorphone, noroxycodone) are less pharmacologically active than morphine's M6G — preferred over morphine in CKD patients requiring strong opioids
  • OxyContin (SR formulation) abuse potential: high lipophilicity and extended-release mechanism — opioid abuse crisis in USA largely driven by OxyContin; UK prescribing should be judicious with clear exit strategy
  • MHRA 2017: Oxycodone + gabapentinoid combination significantly increases fatal respiratory depression — VERY common combination in orthopaedics post-arthroplasty; review all prescriptions
  • Post-arthroplasty opioid stewardship: ERAS goal is opioid-free or opioid-minimal discharge; prescribe defined 5–7 day course, not open-ended; review at follow-up and wean

Contraindications

  • Acute respiratory depression
  • Paralytic ileus
  • Known hypersensitivity to oxycodone

Side effects

  • Constipation — universal; prescribe laxative
  • Nausea and vomiting
  • Sedation
  • Respiratory depression
  • Urinary retention
  • Addiction potential — Schedule 2 CD

Interactions

  • CNS depressants — additive respiratory depression (MHRA warning with gabapentinoids)
  • CYP3A4 inhibitors (ketoconazole, clarithromycin) — increase oxycodone levels; reduce dose
  • CYP2D6 inhibitors (fluoxetine, paroxetine) — reduce conversion of oxycodone to oxymorphone; modest effect

Monitoring

  • Respiratory rate and SpO2
  • Sedation score
  • Pain score
  • Bowel function
  • Signs of dependence (prolonged use)

Reference: BNFc; BNF 90; MHRA DSU 2017 (Gabapentinoids); ERAS Orthopaedic Protocols; BNF Opioid Equivalence Table. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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