SUMMARY According to several guidelines, topical agents should be considered for the pharmacological management of localized neuropathic pain. As a definition for the term 'localized neuropathic pain' that might facilitate easier identification of patients who are putatively responsive to topical treatments could not be found in the literature, six pain specialists met in 2010 to address this challenging issue. The following nucleus of a definition that is based on the International Association for the Study of Pain (IASP) definition of neuropathic pain, is the most detailed that can currently be proposed: 'Localized neuropathic pain is a type of neuropathic pain that is characterized by consistent and circumscribed area(s) of maximum pain'. An extended version of this core definition and the difficulties in covering all aspects of localized neuropathic pain are presented, and discussions within the scientific community are encouraged to develop a definition that might help to identify patients who could benefit most from topical treatment.

The broad analgesic efficacy of tapentadol PR may simplify chronic pain management by allowing for the treatment of different types of pain with a single analgesic. In addition, tapentadol is associated with a low risk of pharmacokinetic interactions, which permits its use in patients taking multiple medications. Furthermore, the favorable tolerability profile of tapentadol PR may result in improved patient compliance and allow for easy titration and rotation from previous strong opioids.

Tapentadol prolonged release (PR) for the treatment of moderate to severe chronic pain combines 2 modes of action. These are μ-opioid receptor agonism and noradrenaline reuptake inhibition in a single molecule that allow higher analgesic potency through modulation of different pharmacological targets within the pain transmitting systems. At the same time, this can also serve as a clue for modulation of different pain-generating mechanisms according to nociceptive, neuropathic, or mixed pain conditions. Tapentadol PR has now been on the market for 5 years, with over 4.6 million people treated worldwide. A panel of pain specialists convened in Germany to review the clinical program and to discuss the role of tapentadol PR in the management of chronic pain. The clinical study program demonstrated effective and generally well-tolerated treatment for up to 2 years in a broad range of chronic pain conditions, including those with neuropathic pain components. This was confirmed in routine clinical practice observations. Head-to-head studies with World Health Organization (WHO) III opioids such as oxycodone controlled release and oxycodone/naloxone PR showed at least comparable pain relief in the treatment of moderate-to-severe musculoskeletal pain. Rotation from poorly tolerated WHO III opioids to tapentadol PR provided effective pain relief and better symptom control for musculoskeletal pain compared to previous medication. Functionality, health status and quality of life also improved under tapentadol PR treatment. The gastrointestinal tolerability profile was more favorable compared to other tested WHO III opioids. Tapentadol PR has a good safety profile and no evidence of acquired tolerance from the long-term data so far collected. Overall, tapentadol PR represents an effective and generally well-tolerated alternative to "classical" opioidergic drugs.

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The capsaicin 8% cutaneous patch is an emergent new treatment option for patients with peripheral neuropathic pain. In randomized controlled clinical studies relevant pain relief for 12 weeks was achieved in about one third of patients following a single application. The first part of this paper is a review of the pathophysiology, pharmacology, and published clinical trials with the capsaicin 8% cutaneous patch. The second part reports on outcomes of an interdisciplinary expert workshop, where new treatment results of three major German pain centers were presented and reviewed with the objectives of obtaining responder rates for different pain syndromes, assessing maintenance of effect under real-life conditions, and giving recommendations for practical care. The 12 week responder rates with pain relief of ≥ 30% were comparable in patients with mononeuropathies (37.9%) and postherpetic neuralgia (38.8%). Similar responder rates were seen in a subgroup of patients with cervical spine radiculopathy and back pain (46.7%). In HIV-associated neuropathy the responder rates were high (47.8%) but lower in patients with other polyneuropathies (17.6%). Response rates were nearly identical after 1 week (46.6%) and 4 weeks (43.3) and dropped only slightly at 12 weeks (37.4%). In a subgroup of 54 patients who underwent a second treatment, efficacy was maintained. Response rates in patients with or without lidocaine pretreatment were comparable. Treatment with the capsaicin 8% cutaneous patch was generally safe and well tolerated. The workshop panel recommended further investigation of opportunities to improve the application procedure and to perform studies on the skin penetration and distribution of capsaicin. A modified quantitative sensory testing (QST) should be developed for clinical practice in order to better understand the correlation of sensory profiles and response to capsaicin treatment.