Umbrella term for multiple disorders, including CRPS, MS, postherpetic neuralgia Symptoms: intermittent pain, hyperpathia (painful stimuli evoke exaggerated levels of pain), and burning pain First-line pharmacologic treatments: TCAs (desipramine, amitriptyline) SNRIs (like duloxetine) gabapentin / pregabalin. Second-line: oral tramadol (partial opioid, partial SNRI) 8% capsaicin patches 5% lidocaine patches. Third-line: strong opioids and botulinum toxin injection. Opioids: caution in elderly Methadone: good option with anti-NMDA and SSRI properties Inconclusive treatments: tapentadol, most antiepileptic drugs, capsaicin cream, topical clonidine, NMDA antagonists, and selective serotonin reuptake inhibitors (SSRI). Weak recommendations against: cannabinoids and valproate Strong recommendations against: levetiracetam and mexiletine NSAIDs: caution in diabetics with renal dysfunction