Opioid-Related Constipation in Patients With Non-cancer Pain Syndromes: a Review of Evidence-Based Therapies and Justification for a Change in Nomenclature.

PURPOSE OF REVIEW: Opioids are a mainstay in the treatment of chronic non-cancer pain syndromes, but their analgesic benefits come at a cost as opioid-related constipation occurs in 40-80% of individuals taking chronic opioids. Furthermore, as 10-20% of the population suffers from constipation at baseline, it should be expected that while a proportion of individuals will develop constipation as a direct consequence of opioids (OIC), others will experience it as an exacerbation of their baseline constipation (OEC). Herein, we review the evidence-based data for treatments directed at opioid-related constipation focusing on individuals with non-cancer pain syndromes and provide a template for the development of differentiated treatment algorithms for OIC and OEC. RECENT FINDINGS: Historical and current treatment protocols recommend traditional laxatives, but these are ineffective in up to 50%, due in part to the heterogeneous pathogenesis of constipation. Therapeutic decisions must be tailored to account for this overlapping pathogenesis. OIC and OEC are distinct entities. As such, additional research and guidelines should address these as different patient populations.