Chronic pain is common, and opioid therapy is often required for pain management. Unfortunately, opioid-induced bowel dysfunction (OIBD) is a frequent and debilitating side-effect of opioid use. A new prolonged-release (PR) preparation of oxycodone/naloxone has been developed for moderate-to-severe pain that reduces OIBD in patients. In this article, we consider the mode of action and efficacy of this combination opioid therapy for chronic pain. C hronic pain, which can be defined as pain that persists or progresses over a prolonged period, 1 is a widespread problem affecting 19% of adults across Europe. 2 In a large-scale telephone sur vey involving 46 394 respondents in 15 European countries and Israel, the most common source of chronic pain was low back pain (24%), which was most often due to osteoarthritis (34%). 2 More in-depth interviews took place with 4839 of those who had reported chronic pain. This showed that 66% had moderate pain assessed by a Visual Analogue Score (VAS) of 5-7 (rating 1 as being no pain and 10 as the worst pain imaginable), 34% had severe pain (VAS of 8-10), 46% had constant pain and 54% had intermittent pain. 2 For many people, the duration of pain was prolonged: 59% had pain for 2-15 years, while 21% had pain for more than 20 years.
CHRONIC PAIN AND USE OF OPIOIDSNonsteroidal anti-inflammator y drugs (NSAIDs), anticonvulsants, antidepressants, membrane stabilisers and opioids are all used to treat chronic pain. Careful dose titration and management of side-effects are essential for optimal pharmacotherapy. The World Health Organization (WHO) recommends opioids for managing moderate-tosevere cancer pain, but the role of opioids in chronic non-cancer pain is less established; they are increasingly being used to treat chronic non-cancer pain. 3 Breivik et al found that only 5% of those taking prescription medications for pain were taking a strong opioid. 2 There may be a need to optimise opioid use for those patients who do not respond to other analgesic regimens including pharmacological and non-drug therapies. Opioids may be useful for neuropathic and nociceptive pain if other strategies fail to provide adequate analgesia within a reasonable time. 4 Opioids are an important treatment option but they must be carefully prescribed and their use managed appropriately.A large meta-analysis of 41 randomised trials involving 6019 patients with nociceptive pain (osteoarthritis, rheumatoid arthritis or back pain), neuropathic pain Prolonged-release oxycodone/ naloxone for chronic pain Naloxone binds selectively to intestinal opioid receptors, without blocking the analgesic effect of oxycodone.
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