Abstract
Chronic pain is a serious public health concern. Under-treatment of chronic pain causes intense physical and psychological suffering and can destroy patient's quality of life.
Experience with long-term opioid analgesia in patients with cancer pain has shown highly favourable risk/benefit ratio. Where standard therapeutical methods have failed, patients can be treated by administration of strong opioids.
However, opioid treatment has its issues. Life expectancy of chronic pain patients is temporarily unlimited and for that reason the time horizon of opioid therapy is unlimited as well.
The effect of opioids on the organism is very complex. In comparison with cancer pain, opioid responsiveness to chronic non-cancer pain is somewhat different.
Clinical experience has shown that exceeding medium-sized doses of opioids in the treatment of chronic non-cancer pain does not lead to further improvement of analgesia, but only increases degree of physical dependency and tolerance. Therefore, from a clinical point of view, opioids in chronic non-cancer pain should be regarded as substances with a ceiling effect.
In some patients medicated with opioids, dependency can appear to be the dominant clinical problem that might be difficult to distinguish from addiction. Management of withdrawal symptoms may enhance pain control, mental state and compliance with pain management.