NEUROPATHIC PAIN OF PERIPHERAL ORIGIN - ADVANCES IN PHARMACOLOGICAL TREATMENT

A variety of mechanisms may generate pain resulting from injury to the peripheral nervous system. None of these mechanisms is disease-specif ic, and several different pain mechanisms may be simultaneously presen t in any one patient, independent of diagnosis. Diagnosis of neuropath ic pain is often easily made from information gathered on neurologic e xamination and from patient history. Evidence of sensory disturbances elicited on examination combined with laboratory tests confirming inju ry to peripheral nerve establishes the diagnosis of neuropathic pain. Although treatment of neuropathic pain may be difficult, optimum treat ment can be achieved if the neurologist has a complete understanding o f the therapeutic options, the mainstay of which is pharmacotherapy. S election of an appropriate pharmacologic agent is by trial and error s ince individual responses to different agents, doses, and serum levels are highly variable. An adequate trial for each agent tried is key to pharmacologic treatment of neuropathic pain. Tricyclic antidepressant s are first-line agents, although other drugs, including anticonvulsan ts, local anesthetic antiarrhythmics, clonidine, opioids, and certain topical agents, also offer pain relief in some patient populations. Th e novel antidepressants venlafaxine and nefazodone are potentially use ful new drugs that are better tolerated than tricyclic antidepressants .