Abstract
Postherpetic neuralgia (PHN) is persistent pain that occurs after the resolution of skin lesions caused by the reactivation of the herpes zoster virus. Several first-line agents, including anticonvulsants, tricyclic antidepressants, and lidocaine patches, are used in treatment. However, systematic, evidence-based, multidisciplinary clinical practice guidelines (CPGs) addressing the use of opioids and pain interventions-such as nerve blocks-for patients with refractory PHN unresponsive to first-line agents have not yet been established. Therefore, the Korean Pain Society, in collaboration with relevant medical specialty societies, has developed de novo CPGs for the management of refractory PHN. The development process followed Cochrane's systematic literature review methodology and employed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the certainty of evidence and strength of recommendations. Key questions, identified through a survey of experts treating patients with refractory PHN, were finalized by the CPGs development panel. A literature search was conducted in four electronic databases: PubMed (MEDLINE), Embase, Cochrane Library, and KoreaMed. Studies were selected based on predefined inclusion and exclusion criteria using the population, intervention, comparison, outcomes, and study design (PICOS) framework. The resulting recommendations integrate evidence from the literature with patient and clinician preferences and values. They also take into account the quality of evidence, the balance of benefits and harms, potential barriers to implementation, and feasibility within various healthcare settings. These evidence-based multidisciplinary CPGs are expected to assist physicians in safely and effectively treating patients with refractory PHN.