Taiwan Expert Guidance for the Diagnosis and Management of Opioid-Induced Constipation.

Opioid-induced constipation (OIC) is among the most frequent and persistent adverse effects of opioid therapy and may reduce analgesic adherence, worsen quality of life, and increase resource use. This article summarizes the 2026 Taiwan expert guidance for the diagnosis and management of OIC, prepared by the Taiwan OIC Advisory Board with multidisciplinary input and reference to international guidelines and Taiwan clinical practice. The guidance recommends the Rome IV criteria as the diagnostic standard, supported by the Bowel Function Index as an adjunctive assessment and monitoring tool, and recommends K59.03, drug-induced constipation, as the principal ICD-10-CM/PCS diagnostic code. Management begins before opioid initiation, with patient and caregiver education, baseline bowel assessment, and prophylactic laxatives in high-risk settings. When OIC is diagnosed, lifestyle measures and stimulant or osmotic laxatives are first-line therapy, with reassessment after one to two weeks. Peripherally acting μ-opioid receptor antagonists, of which naldemedine is currently the available agent in Taiwan, are preferred for laxative-refractory OIC and may be used alone or in combination with laxatives. Persistent symptoms should prompt consideration of opioid adjustment and further evaluation. A practical algorithm is proposed to harmonize OIC recognition, coding, and treatment escalation in Taiwan while remaining adaptable to individual patient needs.