McMaster University

Michael G. DeGroote
National Pain Centre

Scope of Search

Canadian Guideline for Safe and Effective Use of Opioids for Chronic Non-Cancer Pain

Cluster 3: Monitoring Long-Term Opioid Therapy (LTOT)

R12. Recommendation Statement

No. Recommendation Keyword


When monitoring a patient on long-term therapy, ask about and observe for opioid effectiveness, adverse effects or medical complications, and aberrant drug-related behaviours (Grade C).

Monitoring LTOT

  • R12. Discussion

R12. Discussion

1. Opioid Effectiveness

(improved function or at least 30% reduction in pain intensity)

1.1 Evaluate change in pain intensity.

See Recommendation 9.

1.2 Ask about progress in reaching agreed-on goals, an important indicator of function change . Self-report can be prompted by asking about work, household activity, mood, walking ability, sleep, and social activities. For an example of a structured assessment tool frequently used in trials, see Appendix B-9: Brief Pain Inventory©.

1.3 If opioid therapy is not effective, consider switching opioids or discontinuing.

See Recommendation 13.

2. Adverse Effects and Medical Complications

2.1 More common adverse effects include nausea, constipation, drowsiness, dizziness/vertigo, dry-skin/itching/pruritus, and vomiting.

2.2 Medical complications include neuroendocrine abnormalities and erectile dysfunction, sleep apnea and opioid-induced hyperalgesia.

2.3 See Recommendation 5 for detailed information about adverse effects and medical complications.

3. Aberrant Drug-related Behaviours

3.1 Aberrant drug-related behaviours have been divided into three groups (Passik 2004):

  • Escalating the dose (e.g., requesting higher doses, running out early)
  • Altering the route of delivery (e.g., biting, crushing controlled-release tablets, snorting or injecting oral tablets)
  • Engaging in illegal activities (e.g., multiple doctoring, prescription fraud, buying, selling and stealing drugs). See Appendix B-10 for more information on detecting aberrant drug-related behaviours

3.2 Tools designed to recognize aberrant drug-related behaviours may be useful in determining a patient’s misuse of opioids. See Appendix B-11 for available tools including two examples, SOAPP®-R and COMM®.

4. Physician-Pharmacist Collaboration

4.1 A complete prescription history in one location can facilitate monitoring and support physician-pharmacist collaboration. Physicians can enable this by encouraging patients to select a single pharmacy to have prescriptions filled.

4.2 Pharmacists, through their multiple interactions with the patient, can:

  • Reinforce patient education about safe, appropriate use of opioids
  • Observe for behaviours or adverse effects that should be communicated to the physician (Also see Recommendation 14, LTOT and driving.)
  • Alert physicians to concerns about potential misuse (Also see Recommendation 22, Prescription fraud.)