Opioids, Clinical Opioid Tolerance

Synonyms

Analgesic tolerance; Opioid tolerance

Definition

Tolerance is the term used to define the phenomenon in which an organism is less susceptible to the effect of a drug as a consequence of its prior administration (Foley 1993; Management of Cancer Pain Guideline Panel 1994).

Characteristics

Though the definition of tolerance is relatively straightforward, tolerance to opioids is the need to increase dose requirements over time to maintain pain relief (Management of Cancer Pain Guideline Panel 1994). There are many clinical circumstances when opioid tolerance is suspected, and defining opioid analgesic tolerance in a clinical setting is much more subtle and certainly more challenging. This entry is a review of the issues and questions rather than a source of answers, and this is largely because the evidence-based publications addressing this topic are lacking, and consensus statements related to opioids by experts and professional societies are thus far focused on regulatory...