Oral oxycodone MR (Longtec) for acute pain
- This is a modified release formulation of oxycodone hydrochloride, a mu and kappa opioid receptor agonist.
- It has a much higher oral bioavailability than other opioids resulting in a better predictability of effect.
- The modified, or controlled, release allows a rapid onset of effective analgesia (approximately 40 minutes), which is sustained for 12 hours.
- Twice daily dosing maintains steady state therapeutic plasma levels after 2 - 3 doses.
- Oxycodone MR tablets must not be crushed for patients who cannot swallow or for administration through nasogastric/jejunal tubes. This may result in dangerously high plasma levels due to rapid absorption of a high dose.
- Oxycodone MR is indicated for the management of postoperative pain, severe pain (moderate to severe pain in palliative care). Patients should be prescribed a multimodal analgesic regime where possible. Consider using NSAID’s or COX-2 inhibitors and paracetamol along with oxycodone.
- Availability: 5mg, 10mg, 20mg tablets (also 15, 30, 40, 60, 80, 120mg)
Dosing:
Starting dose - usually 10mg or 20mg 12 hourly- Use lower dose in the elderly, hepatic or renal impairment.
- Avoid if breast feeding.
- Titrate dose to achieve mild or no pain.
- Above 20mg it may be increased by 25% at each dose change.
- Do not change dose frequency from 12 hourly.
Converting IV morphine to PO oxycodone MR (see opioid equivalence)*
Take the following steps:
- The total 24 hour oxycodone MR dose = 1.3 x previous 24 hr parenteral morphine consumption.
- Then divide the calculated total 24h oxycodone MR dose by 2 (to obtain the 12 hourly dose).
- Then round down to appropriate tablet strength.
- Immediate release oxycodone may be prescribed for breakthrough pain. The recommended dose is one fifth to one sixth of the 24 hourly oxycodone MR dose. This is available as capsules or liquid (for doses under 5mg). If more than 2 doses are required within 24 hours consider titrating the oxycodone MR dose upwards.
- As with other opioids, it is good practice to prescribe two antiemetics with oxycodone and consider regular laxative prescription.
Side effects, contraindications and monitoring
As for other opioids, regularly review need for opioid, e.g. post-operatively, if not previously taking long-term.
If being discharged home on newly prescribed strong opioids, advice to be obtained from the Acute Pain Service for opioid dose reduction and discontinuation. APS will provide a completed proforma detailing instructions for primary care.
*NOTE - Care is needed with dose equivalence and conversion (oxycodone and morphine have different opioid potencies)
- 6.6mg PO oxycodone MR is approx equivalent to 5mg parenteral morphine
- 10mg PO morphine is approx equivalent to 5mg parenteral morphine (BNF 70)