Pharmacological management of incident pain in palliative care

If incident pain can be anticipated, give the analgesic sufficient time to take effect before the activity.

Pharmacological management of incident pain can include a nonsteroidal anti-inflammatory drug (NSAID) or an opioid.

If an opioid is used, select an immediate-release formulation with a short onset of action and ideally a duration of action to match the duration of the activity anticipated to cause pain. Calculate the initial dose of the opioid as for breakthrough pain. If this dose is inadequate, consider increasing the dose, or using a nonopioid drug either in combination with or instead of the opioid. However, be aware that high doses of drugs for incident pain can lead to oversedation once the activity causing pain has finished.

Patients experiencing incident pain who take regular opioid therapy do not require the regular opioid dose to be increased based on the doses of analgesics used to manage incident pain (in contrast, opioid doses used for breakthrough pain are used to determine an increase in dose of regular therapy).

A rapid-acting drug may be helpful just before brief painful activities. For example, transmucosal fentanyl may help with frequent activities (eg being turned in bed). Methoxyflurane should not be used regularly but may be used for infrequent activities (eg dressing changes)—seek expert advice.

Sometimes an anxiolytic may provide benefit for patients with incident pain (eg before performing a procedure such as a complex wound dressing or digital disimpaction of faeces). Use caution when combining an opioid with a benzodiazepine to prevent incident pain because there is an increased risk of respiratory depression; minimise this risk by carefully adjusting the opioid dose and using a judicious benzodiazepine dose.

Incident pain and procedure-related pain have many similar features; for information on management of procedure-related pain, see Procedural sedation and analgesia in the Pain and Analgesia guidelines.

If the above measures are not effective, consider epidural or intrathecal anaesthesia—seek specialist palliative care advice.

See Pharmacological management of pain in palliative care for general information.