Abstract
The multitude of treatments available for tens of millions of US adults with moderate/severe chronic pain have limited efficacy. Long-term opioid therapy (LTOT) is a widely available option for controlling pain among patients with chronic pain refractory to other treatments. The recent recognition of LTOT inefficacy and complications has led to more frequent opioid tapering, which in turn has revealed its own set of complications. The occurrence of the same set of symptoms-worsening pain, declining function, and clinical instability-in contrasting contexts of LTOT ineffectiveness and opioid tapering has led to increasing recognition of the utility of complex persistent opioid dependence (CPOD), a clinically distinct but biologically similar state compared with opioid use disorder as an explanatory diagnosis/heuristic. Recent guidelines for LTOT tapering have incorporated buprenorphine treatment based on CPOD concepts as a recommended treatment for problems due to opioid tapering with limited supportive evidence. The increasing utilization of buprenorphine for both LTOT ineffectiveness and opioid tapering problems raises the urgent need for a review of the clinical definition, mechanisms, and treatment of CPOD and pertinent policies. In this manuscript, we discuss various issues related to CPOD that requires further clarification through research and policy development.