Sometimes when medical treatments work so well, we don't study them as we should.  This has been the story of opioids.  Opioid analgesics work amazingly well for acute pain.  For chronic pain, it's a mixed bag.  For some chronic pain syndromes, anticonvulsants, antidepressants and/or NSAIDS are sufficient.  One alone doesn't work, add a 2nd....Thereafter, a trial of opioids may be considered. For neuropathic pain, there is some evidence that opioids are effective.  However, long term effects of opioids are difficult to ascertain.  Few prospective studies exist.  Long term effects of chronic pain (and for whatever condition being treated) must be teased out from possible long term effects of opioid use (exclusive of risk of addiction).  Most patients would gladly accept all the risks if round the clock analgesia were possible.  Properly supervised, the risk of addiction can be minimized.  We are extremely short of pain specialists & tertiary pain clinics in Ontario.