Pain Medicine and Palliative Care
What to know
Pain questions test mechanism-based thinking. Distinguish nociceptive (somatic/visceral) from neuropathic (burning, shooting, allodynia) and central pain. Know the WHO analgesic ladder and its modern interpretation, opioid principles (titration, breakthrough dosing, rotation, equianalgesia), and adjuvant drugs (gabapentinoids, tricyclics, SNRIs, ketamine, corticosteroids). Understand opioid side effects (respiratory depression, constipation, tolerance, hyperalgesia) and the principles of palliative care: symptom control, goals of care, communication, and end-of-life prescribing (anticipatory prescribing for pain, dyspnoea, agitation, secretions).
Traps
- Assuming neuropathic pain responds to simple analgesics - it needs adjuvants.
- Forgetting that opioid rotation requires equianalgesic conversion and dose reduction for incomplete cross-tolerance.
- Missing that constipation does not develop tolerance (unlike nausea and sedation), so prophylaxis is needed.
- Confusing palliative sedation with euthanasia - intent and proportionality matter.
Rule of thumb
Match drug class to mechanism: nociceptive → paracetamol/NSAID/opioid; neuropathic → gabapentinoid/tricyclic/SNRI; and always reassess with a validated tool.
Worked example
A patient on morphine develops neuropathic burning pain. Add a gabapentinoid or tricyclic rather than escalating morphine alone, because the mechanism is neuropathic and opioid responsiveness is limited.