Breakthrough Pain in Chronic Non-Cancer Pain: Fact, Fiction, or Abuse

Treatment of chronic non-cancer pain with opioid therapy has escalated in recent years,resulting in exploding therapeutic use and misuse of prescription opioids and multipleadverse drug events. Breakthrough pain is defined as a transient exacerbation of painexperienced by individuals who have relatively stable and adequately controlled baselinecancer pain. Further, the definition of breakthrough pain, prevalence, characteristics,implications, and treatment modalities have been extensively described for chroniccancer pain. However, the literature for breakthrough pain in chronic non-cancer painincluding its terminology, prevalence, relevance, characteristics, and treatments, havebeen poorly described and continue to be debated.The philosophy of breakthrough pain in chronic non-cancer pain raises multipleissues leading almost all patients to be on high dose long-acting opioids, followed bysupplementing with short-acting drugs, instead of treating the patients with only shortacting drugs as required. Consequently, the subject of breakthrough pain in chronicnon-cancer pain is looked at with suspicion due to the lack of evidence and inherent biasassociated with its evaluation, followed by escalating use and abuse of opioids.Multiple issues related to the concept of breakthrough pain in chronic non-cancerpain evolve around extensive use, overuse, misuse, and abuse of opioids. In the era ofeliminating opioids or significantly curtailing their use to only appropriate indications, theconcept of breakthrough pain raises multiple questions without any scientific evidence.This review illustrates that there is no significant evidence for any type of breakthroughpain in chronic non-cancer pain based on available literature, methodology utilized, andresponse to opioids in chronic non-cancer pain. The advocacy for increased usage ofopioids in the treatment of chronic pain dates back to the liberalization of laws governingopioid prescription for the treatment of chronic non-cancer pain by state medical boardsin the late 1990s, and is exploding with new pain management standards for inpatientand outpatient medical care implemented by the Joint Commission on Accreditationof Health Care Organizations in 2000, and the advocacy by many physicians andorganizations for increased use of opioids.This comprehensive review critically evaluates the available evidence of breakthroughpain in chronic non-cancer pain including its existence, prevalence, and managingsymptoms which are described as breakthrough pain or episodic pain.Key words: Breakthrough pain, opioids, chronic non-cancer pain, opioid abuse, opioidmisuse, addiction, opioid hyperalgesia, interventional techniques