Oxycodone
Second line strong opioid, use only if intolerance to morphine
Mechanism of action: mu-opioid agonist
Presentation:
- Oral:
- Immediate release (IR) available as oral solution (OxyNorm, Shortec) or capsules (OxyNorm, Shortec, Lynlor)
- Modified release (MR) available as tablet (e.g., OxyContin, Longtec, and various others: please see BNF).
- Solution for injection for subcutaneous or intravenous bolus and patient controlled analgesia.
Dose: Approximately 1.5 to 2 times stronger than morphine.
Suggested initial dose: immediate release oxycodone 5-10mg orally 4 hourly prn for adults over 50kg with normal hepatic and renal function; reduce in frailty. Increase dose as necessary if pain is poorly controlled. [Licensed for 4 hourly interval, in contrast to immediate release morphine which is licensed for a 2 hourly interval].
Modified release opioid preparations should not be initiated for patients with acute pain.
Monitor all patients for opioid toxicity using sedation score and respiratory rate. The risk of opioid-induced ventilatory impairment is increased if other sedatives are co-prescribed, including benzodiazepines and gabapentinoids, and by the use of modified release preparations in opioid naive patients. Monitor renal impairment as any deterioration will increase the risk of opioid accumulation.
If unreliable enteral absorption, consider oxycodone PCA or 2.5-5mg subcutaneous injection 4 hourly prn
Co-prescribe prn Naloxone
Oral absorption: Well absorbed. Bioavailability of 60-80%
Protein binding: 45%
Metabolism: Hepatic. Metabolized by CYP2D6 to oxymorphone, and by CYP3A4 to noroxycodone, both of which have analgesic activity.
Elimination: primarily via the kidney
Half-life: 3-5 hours
Further prescribing information (side effects, contraindications, interactions):