Opioids and long-lasting pain conditions:: 25-year perspective on mechanism-based treatment strategies

The strategy for pain treatment has to be tailored to the pain diagnosis, not to diagnosis of the disease. A specific clinical pain analysis should replace the routine-like fashion by which treatment programmes are commonly applied. such as the World Health Organization analgesic ladder, which is based mainly on pain intensity. A recent call for the development of a mechanism-based classification of pain seems to be most relevant in this perspective; this is discussed, with the additional aim of suggesting a replacement of the current syndrome-based International Association for the Study of Pain classification, in which, for example. neither cancer pain nor chronic pain can any longer be accepted as entities for clinical research protocols without further specification. There is a great need for the application of new standardized clinical approaches to pain analysis, such as sensory and pharmacological tests as a mandatory prerequisite for the choice of any type of pain treatment if specific modulation of the pain itself is the goal. Current views on opioid sensitivity are also discussed, focusing on a suggestion that various forms of pain or pain components are differentially sensitive, conceivably reflecting the presence of different pain generating mechanisms. The design of a pain analysis with emphasis on the pathophysiology of the transmission of the pain and its endogenous control constitutes a basis for a new concept in pain management that has, so far, not been adequately adopted in current clinical pain research, most often owing to a lack of differentiation between affective and sensory analgesia.