Opioid-induced constipation: Update on management and treatment

Opioids are effective for acute and chronic pain management and are therefore an important treatment option for supportive care, especially in patients with cancer. They often induce digestive adverse effects, the most frequent being opioid-induced constipation (OIC), which is related to their action on μ receptors in the gastro-intestinal tract. These receptors play a role in the regulation of the gut motility and secretions. OIC has frequently been overlooked, although it can impair patients’ comfort and compromise their compliance with opioid treatment. The consensus definition of OIC was established in 2016, and targeted therapies, the peripherally acting μ-opioid receptor antagonist (PAMORA) can yet specifically treat OIC without compromising pain relief. This review aims to explore the definition, pathophysiology, epidemiology, and diagnostic criteria of OIC. Risk factors and the necessary testing for the diagnostic work-up will be detailed. Finally, the impact of OIC on opioid treatment will be explained, and the treatment options, including non-pharmacological treatments, and pharmacological first-line and second-line therapies will be developed. A summary of the current therapeutic recommendations will be provided.