Opioids are complex drugs that produce profit (most importantly
analgesia) as well as a myriad of adverse effects including gastrointestinal motility disturbances, abuse and addiction, sedation and potentially lethal
respiratory depression (RD). Consequently,
opioid treatment requires careful evaluation in terms of benefit on the one hand and harm on the other. Considering benefit and harm from an economic perspective,
opioid treatment should lead to profit maximization with decision theory defining utility as (profit - loss). We here focus on the most devastating
opioid adverse effect, RD and define
opioid utility U = P(benefit) - P(harm), where P(benefit) is the probability of
opioid-induced
analgesia and P(harm) the probability of
opioid-induced RD. Other utility functions are also discussed including the utility U = P(benefit AND NOT harm), the most wanted
opioid effect, i.e.,
analgesia without RD, and utility surfaces, which depict the continuum of probabilities of presence or absence of
analgesia in combination with the presence or absence of RD. Utility functions are constructed from pharmacokinetic and pharmacodynamic data sets, although pragmatic utility functions may be constructed when pharmacokinetic data are not available. We here discuss utilities of several
opioids including the partial
mu-opioid-receptor agonist
buprenorphine, the full
opioid receptor agonists
fentanyl and
alfentanil, and the bifunctional
opioid cebranopadol, which acts at mu-
opioid and nociception/
orphanin FQ-receptors. We argue that utility functions give clinicians the opportunity to make an informed decision when
opioid analgesics are needed for
pain relief, in which
opioids with a positive utility function are preferred over
opioids with negative functions. Furthermore, utility functions of subpopulations will give an extra insight as a utility functions measured in one subgroup (e.g., patients with
postoperative pain, good
opioid responders) may not be mirrored in other patient subgroups (e.g.,
neuropathic pain patients, poor
opioid responders).