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Neuropathic pain is a common and difficult to manage public health problem characterized by frequent treatment failure and high management costs. The variable presentation and response to treatment among patients make it difficult for physicians to apply a single, standardized approach for management. The physician's role in treating neuropathic pain is complex. Clinical decisions must be drawn from personal and shared experience, case reports, and evidence-based, controlled trials performed on selected populations of patients with common, narrowly-defined conditions. Recent advances in our understanding of the mechanisms that underlie the processing of nociceptive stimuli and the perception of pain have led to the increased ‘off-label use’ of adjuvant medications in an attempt to provide relief for many patients who heretofore have suffered unnecessarily with intractable neuropathic pain. Unfortunately, as with any treatment, sound clinical decisions can occasionally result in an untoward adverse response. It is therefore imperative that potential adverse effects inherent to all medications be considered and weighed against the untoward consequences of withholding treatment prior to incorporating their use in any course of management. This commentary presents a case report that illustrates a particularly devastating consequence that was encountered when a medication was selected for ‘off-label use’ in the treatment of intractable pain and presents an opinion for consideration in developing guidelines for determining acceptable risk and standard of care based upon rational adherence or deviation from the approved indications offered for the use of a medication at the time of its introduction into practice is granted.

Inflammation causes upregulation of NaV1.7 sodium channels in the associated dorsal root ganglia (DRG). The resultant increase in sodium influx must be countered to maintain osmotic homeostasis. The primary mechanism to pump sodium out of neurons is Na(+), K(+)-ATPase. To test whether there is a compensatory upregulation of Na(+), K(+)-ATPase after inflammation, rats received an injection of complete Freund's adjuvant (CFA) into one hindpaw and saline into the contralateral hindpaw. Three days later, L4-L6 DRGs were extracted and analyzed using gel electrophoresis and immunohistochemistry. Immunoreactivity for both the α-1 and α-3 subunits were increased in DRG associated with CFA-treatment, compared to saline-treatment. To test whether dysregulation of Na(+), K(+)-ATPase may cause cell death after inflammation, we produced a pharmacological blockade with ouabain (10mg/kg, s.c.) three days after CFA injection and paws were stimulated or not. Twenty-four hours later, DRG were removed and stained with cresyl violet. Greater cell death was seen in DRG from ouabain-treated animals on the CFA treated side than the saline-treated side. Paw stimulation doubled this difference. Control DRG showed little neuronal death. These results are evidence that regulation of Na(+), K(+)-ATPase during major inflammatory disease states is critical for homeostatic protection of primary afferent neurons.