Chronic Pain and Decreased Opioid Efficacy: An Inflammatory Link.

Chronic pain is a devastating amalgam of symptoms that affects millions of Americans at tremendous cost to our healthcare system and, more importantly, to patients' quality of life. Literature and research demonstrate that neuroimmune cells called glia are not only responsible for initiating and maintaining part of the chronic pain disease process, but also release inflammatory molecules responsible for decreasing the efficacy of one of the most prominent treatments for pain, opioid analgesia. This article describes chronic pain as a disease process that has ineffective treatment modalities, explores the mechanisms of glial cell activation and inflammatory responses that lead to chronic pain and decreased opioid treatment efficacy, and hypothesizes novel chronic pain treatment modalities based on the glial cell inactivation and anti-inflammatory pathways.