Introduction: chronic pain studies of the lidocaine patch 5% using the Neuropathic Pain Scale.

The manifestation of pain in any individual patient may result from a variety of underlying mechanisms that also may vary from one disease state to another. Global measures of pain intensity and relief are inadequate for characterizing specific pain qualities or identifying the unique effects of pain treatments on different pain qualities. The Neuropathic Pain Scale (NPS) is a recently developed measure designed to assess distinct pain qualities and may allow differentiation of therapeutic effects, even in cases where global pain response may be similar. Three studies are presented that provide preliminary evidence for the utility of the NPS for characterizing distinct pain qualities and changes in pain qualities in patients treated with the lidocaine patch 5% for a variety of neuropathic and non-neuropathic chronic pain conditions, including low-back pain, osteoarthritis, post-herpetic neuralgia, and painful diabetic neuropathy.