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Methylnaltrexone: treatment for opioid-induced constipation
Nerissa Licup1, Steven J Baumrucker
1Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA.
Abstract:
Opioids have become the gold standard for treatment of severe pain in advanced disease, but adverse effects can affect the quality of life. Opioid-induced bowel dysfunction can lead to refractory constipation. Methylnaltrexone bromide is a peripherally acting mu antagonist and is indicated for the treatment of opioid-induced constipation in patients with advanced illness, when response to standard laxative therapy has been inefficacious. This pharmacology update will review the etiology, pathophysiology, and treatment of opioid-induced constipation, focused on methylnaltrexone as a novel treatment for refractory cases.
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