Chronic Pain Medicine
What you must understand
Chronic pain is biopsychosocial. Know the difference between nociceptive, neuropathic, and centralized pain, and how each is treated. Understand the pharmacology of chronic pain: NSAIDs, acetaminophen, opioids (with risks of tolerance, dependence, and opioid-induced hyperalgesia), adjuvants (gabapentinoids, tricyclics, SNRIs), and topical agents. Learn interventional options (nerve blocks, radiofrequency ablation, spinal cord stimulation) and their indications. Understand opioid stewardship, risk assessment, and multimodal strategies. Recognize specific syndromes: complex regional pain syndrome, phantom limb pain, and low back pain with radiculopathy.
Traps in questions
Common traps: assuming all chronic pain responds to opioids (neuropathic pain often responds better to gabapentinoids or tricyclics); confusing tolerance with addiction; and forgetting that opioid-induced hyperalgesia can worsen pain with dose escalation. Watch for CRPS questions - early recognition and multimodal treatment matter. Also be careful with gabapentinoids in renal impairment (dose adjust).
Rule of thumb
Match the mechanism: nociceptive → NSAIDs/acetaminophen/opioids; neuropathic → gabapentinoids, tricyclics, SNRIs; centralized → multidisciplinary and behavioral approaches. Always reassess function, not just pain score.
Worked example: A patient with diabetic neuropathy has burning foot pain. First-line options include gabapentin or pregabalin (adjust for renal function) and duloxetine; opioids are not first-line.