Reviewing analgesia efficacy for chronic noncancer pain
The patient’s prescriber is responsible for completing regular review of analgesic efficacy. An analgesic is considered effective for chronic noncancer pain if the patient has:
- achieved at least a 30% reduction in pain
- improved engagement in physical, social and vocational rehabilitation (ie establishing self-management)
- limited or tolerable adverse effects
- no aberrant behaviour.
|
Indicator |
Considerations |
|---|---|
|
Improved analgesia [NB2] |
Has the pain intensity reduced by at least 30%? |
|
Increased activity |
Has physical activity increased since analgesic initiation? Are activity management goals being reached? |
|
Improved affect (mood) |
Has there been an improvement in emotional functioning? |
|
Limited or tolerable adverse effects [NB2] |
Consider a dose reduction, switching to another opioid or deprescribing if adverse effects are intolerable. |
|
No aberrant behaviours [NB2] |
Signs of aberrant behaviour include:
If aberrant behaviours are noted, analgesics should be deprescribed, or therapeutic boundaries tightened (eg dispensing smaller amounts of medication from the pharmacy). |
Note:
NB1: All indicators must be met for an analgesic to be considered effective. NB2: These indicators may be apparent immediately following drug administration. | |
It is often difficult to attribute benefit to a single intervention (eg an analgesic) because an improvement in function or pain may be due to the analgesic, placebo effect or concurrent self-management strategies. Deprescribing is a useful strategy to test whether the benefit is attributable to the analgesic.
In adults, the PEG scale1 is often used to evaluate a patient’s response to analgesics because it assesses analgesia, activity and affect. A 30% reduction in the PEG score indicates that the analgesic may have been successful. If the trial has been unsuccessful (ie a reduction of less than 30% in the PEG score) then the analgesic should be stopped. See here for deprescribing strategies.