Extremes of Pain

Chapter 17 covers the range of extreme and unusual pain-associated conditions by highlighted selected conditions that illustrate the extent of severe pain and informative aberrations in pain signaling, including congenital insensitivity. Multiple forms of severe intractable pain are addressed, including trigeminal neuralgia, postherpetic neuralgia, phantom limb pain, complex regional pain syndrome, peripheral nerve vasculitis, fibromyalgia, Ehlers-Danlos syndrome, stiff-person syndrome, endometriosis, and erythromelalgia. The preponderance of these conditions are neuropathic in nature, and all require coordinated pharmacologic and nonpharmacologic treatment. Pharmacologic therapies may include neuromodulating agents, and nonpharmacologic approaches may include clinical psychology, psychologically informed physical therapy, daily moderate exercise, stress management, sleep optimization, and mind–body approaches. These extreme pain conditions range from fairly prevalent but poorly understood (e.g., fibromyalgia) to rare but associated with specific molecular processes, as in erythromelalgia.