Medication

• If 3 or more oral doses have been missed for any reason, contact SUS for advice on reintroduction dose.
• If the oral route is not available, methadone can be administered as a continuous subcutaneous infusion (CSCI) under the guidance of SPC.  Usual practice would be to convert to a CSCI of methadone at 50% of the daily oral dose. This should be diluted in 0.9% saline and administered in a syringe without any other drugs over 24 hours.
• Occasionally a CSCI may not be appropriate, in which case, Methadone MAT could be administered at 50% of the daily oral dose split into twice daily subcutaneous bolus injections instead. Please seek specialist advice if considering this.

• Buprenorphine MAT is typically used at higher doses than buprenorphine in the palliative care setting which can result in antagonism when other opioids are required.
• Anecdotally antagonism could occur with daily doses of 8mg or more.
• A switch from buprenorphine MAT to methadone MAT guided by SUS could be considered if antagonism is a concern.
• There is increasing use of long-acting subcutaneous buprenorphine preparations for MAT such as Buvidal® which last for up to 4 weeks.
• Where opioid analgesia is required alongside buprenorphine MAT, SPC will consider use of opioids with a high mu-opioid receptor affinity (for example, fentanyl and alfentanil).
• Titration of short-acting opioids to the desired analgesic effect in those treated with Buvidal® might require higher doses. This should be discussed with SPC and closely monitored.
• If the oral route is lost when using oral buprenorphine MAT, SPC should liaise with SUS and advise on the most appropriate alternative opioid and/or route.

• Immediate release preparations of opioids (‘breakthrough doses’) may be best kept to a minimum, with titration of the background opioid preferred.
• The MAT dose should not routinely be used when calculating the appropriate breakthrough dose for symptom control.
• Multiple breakthrough dose usage may represent inappropriate use or undertreated pain.

• Non-opioid analgesics should be considered as adjuvants when appropriate, but not as substitutes for strong opioids.
• There is potential for misuse of adjuvants, especially gabapentin and pregabalin. Consider Amitriptyline first line.
• Non-pharmacological interventions such as radiotherapy, surgery and regional anaesthetic techniques should be considered.

Where clinically indicated, consider the use of benzodiazepines and seek advice from SPC. Benzodiazepines would usually be introduced cautiously and titrated as required. There may be a degree of tolerance if there is a history of non-prescribed use, but this can be difficult to predict.

• When an individual is in the last days of life, Take-Home Naloxone intended for opioid overdose may no longer be appropriate and if administered, could result in severe exacerbation of pain. Individuals and carers may require education around this.
• If the oral route is lost, recently consumed substances could be replaced to avoid withdrawal. This may include the use of parenteral benzodiazepines and opioids.
• Trauma, challenging social circumstances and mental ill-health frequently experienced by PWUD may increase the risk of terminal agitation.

The rules over medication use in certain institutions such as prisons or homeless units may impact management.  Liaison between HCPs and staff may allow a solution to be facilitated on a case-by-case basis.