Clinical drug investigation
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Opioids are the most powerful analgesic drugs currently available and consequently form an essential part of the treatment options for malignant and non-malignant chronic pain. However, the benefits of these medications can be offset by gastrointestinal adverse events such as nausea, vomiting and constipation, as well as adverse events affecting the CNS. These occur relatively frequently in patients receiving long-term opioids for pain relief and are a cause of additional patient suffering and reduced work and social functioning, measured as reductions in quality-of-life outcomes. ⋯ Estimated preference ratings, providing an insight into the trade-off between effective pain control and adverse events, have shown that utility decrements associated with an increase in adverse-event severity were similar in size to those caused by a shift from well controlled to poorly controlled pain. Given the rising prevalence of chronic pain conditions (affecting one in five adult Europeans), the direct and indirect costs incurred from the management of adverse events with long-term opioids are likely to be multiplied, contributing to the socioeconomic burden of chronic pain. For this reason, the adverse-event profile of opioid-based analgesics should be improved to achieve more efficient long-term pain control.