Substance misuse: pain management in palliative care
There are no reliable data on the number of patients treated by palliative care services with recognised drug addiction problems. Addiction behaviour, like most other behaviours, exists on a spectrum and significant under-recognition of drug dependency (in particular alcohol) by palliative care professionals is common . This is compounded by the lack of specific training and a fear of challenging patients with addiction issues who also have advanced life threatening disease. Despite this, palliative care professionals must not ignore addiction behaviour.
The principles of analgesic practice in substance misusers are fundamentally no different from those for other adult patients needing palliative care. Substance misuse is a risk factor for other medical conditions and is also a cause and an effect of psychological difficulties or psychiatric illness. Patients may lack organisational skills to follow complex dosing regimens and vary in their ability to attend clinic for regular follow-up. Staff concerns about their personal safety are a serious consideration when behaviour becomes abusive, and clear boundaries for behaviour require unequivocal explanation whilst maintaining a focus on rational therapeutic plans for care.
Titration of non-opioid, opioid and adjuvant analgesics should be regulated against analgesic response in the usual way; distinctions between symptoms of poor analgesic response and withdrawal should be recognised. Avoiding rapid onset opioids in patients who can still swallow oral medication (eg, buccal fentanyl, subcutaneous diamorphine injections) and agreeing rules on ‘rescue doses’ can help to maintain control over the situation by the clinical team.
Addicted patients may receive maintenance therapy from a substance misuse service and this should be regarded as a separate prescription from that for analgesia when attending as an outpatient. Drug misusers will commonly receive all their medication from inpatient units during an admission, but a clear plan for separate follow-ups for substance misuse and symptom palliation should be in place on discharge except during the terminal phase of an illness. Diversion and misuse of opioids by other family members is not uncommon among patients in palliative care and so the clinical term should be alert to these risks when prescribing for patients at home. Strategies to mitigate this risk include providing short duration prescriptions (eg, 2 days) and storing opioids in locked boxes within the patient’s home.