title: Methylnaltrexone: treatment for opioid-induced constipation.
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.
authors.affiliation: Department of Internal Medicine, East Tennessee State University, Quillen College of Medicine, Johnson City, TN, USA.
authors.forename: Nerissa
authors.initials: N
authors.lastname: Licup
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Baumrucker
mesh_terms: D000701:Analgesics, Opioid / Q000009:adverse effects* / Q000627:therapeutic use; D003248:Constipation / Q000139:chemically induced* / Q000188:drug therapy*; D003672:Defecation / Q000187:drug effects*; D006801:Humans; D009271:Naltrexone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000627:therapeutic use*; D010148:Intractable Pain / Q000188:drug therapy; D010166:Palliative Care / Q000379:methods; D011788:Quality of Life; D000644:Quaternary Ammonium Compounds / Q000627:therapeutic use
chemical_list: D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D000644:Quaternary Ammonium Compounds; C032257:methylnaltrexone; D009271:Naltrexone