Opioid-induced hyperalgesia: the primary care physician’s perspective

Opioid-induced hyperalgesia (OIH) is a state of paradoxical nociceptive sensitization caused by prolonged exposure to opioids. Despite the accumulation of compelling evidence in preclinical studies demonstrating this phenomenon, the clinical impact of these findings remains uncertain. OIH may explain reduced opioid efficacy in some patients; however, it can be difficult to distinguish from other entities including opioid tolerance and underlying disease progression. The purpose of this project was to survey prescribers to review their awareness of, diagnostic approach to and treatment practices for patients suspected of having OIH. Primary care physicians (PCPs) practicing in Boston, Massachusetts were invited to participate. The two-page survey was based on reports previously conducted to survey physicians about chronic opioid therapy. The survey was completed by 100 physicians; 74% of whom practiced at a university/teaching hospital and 26% of whom were in a group practice. Fifty-five percent reported they had treated a patient with OIH. The most common signs used to identify individuals with OIH were increased sensitivity to non-painful stimuli (75%), increased pain despite increased opioid dosage (62%) and decreased opioid effectiveness (42%). For management, 33 respondents employed opioid rotation. Of those who used a rotation, 13 (39.4%) used methadone, 11 (33.3%) used another long-acting oral opioid, 6 (18.2%) used a fentanyl patch and 3 (9.1%) used an immediate-release opiate. Adjunct medication was employed by 38% of physicians. Overwhelmingly, patients with suspected OIH were referred to a pain medicine specialist (90%). This is the first study, to our knowledge, exploring the awareness and practice habits of PCPs regarding OIH. The results of this survey underscore the prevalence of OIH among patients receiving opioid therapy. They also highlight the important role pain management specialists play in the care of these patients: The vast majority of PCPs employ consultation as a means of managing this condition.