查看文章

Opioids produce analgesic effects through their modulatory role in nociceptive transmission. Under many circumstances opioids are the most efficacious analgesics commonly used in the clinical management of moderate to severe pain. Besides the known side effects, opioid treatment is associated with the development of tolerance to and dependence on opioid analgesics. A notable feature of opioid dependence is that hyperalgesic responses may occur both in animals and human subjects during a precipitated opioid withdrawal. This observation suggests that a pronociceptive process may have developed during opioid treatment, which may be unmasked following an opioid withdrawal.

Over the last several years, compelling evidence has accumulated indicating that abnormal pain sensitivity including hyperalgesia and allodynia occurs in animals receiving opioid administration even in the absence of overt …