Naturally occurring opioids (or opiates) have been used for pain relief for millennia and modern drugs that activate opioid receptors are first line in the management of acute spinal pain after injury or operation. However, opioids such as morphine, fentanyl and oxycodone may not be effective for chronic spinal pain.
Opioids may be considered one of the most important classes of dug in clinical practice and their dose may be titrated according to severity. However, their use may also be associated with the development of tolerance (lack of benefit over time) as well as nausea, vomiting, constipation, potential respiratory depression and also withdrawal effects. Other recently discovered side effects of opioids include hypersensitivity to pain, immune suppression, osteoporosis, cognitive impairment and hypogonadism.
While opioids can be effective for spinal pain, a significant proportion of cases are opioid resistant. While opioids are a mainstay of clinical practice for pain relief after operations, an over-reliance on them to the exclusion of other therapeutic options appears to be detrimental in some patients.
A useful website for patients: https://www.rcoa.ac.uk/node/21133