methylnaltrexone bromide

methylnaltrexone bromide


Pharmacologic class: Mu-opioid receptor antagonist (peripherally acting)

Therapeutic class: Opioid

Pregnancy risk category B


Selectively antagonizes opioid binding at mu-opioid receptors (such as those in GI tract) while having restricted ability to cross blood-brain barrier, thereby decreasing constipating effects of opioids without altering analgesic effects on CNS


Solution for injection: 12 mg/0.6 ml in single-use vials

Indications and dosages

Opioid-induced constipation in patients with advanced illness who are receiving palliative care and haven't responded adequately to laxatives

Adults weighing 62 to less than 114 kg (136 to less than 251 lb): 12 mg subcutaneously every other day as needed, but no more frequently than one dose in 24 hours

Adults weighing 38 to less than 62 kg (84 to less than 136 lb): 8 mg subcutaneously every other day as needed, but no more frequently than one dose in 24 hours

Adults weighing outside above ranges: 0.15 mg/kg subcutaneously every other day as needed, but no more frequently than one dose in 24 hours

Dosage adjustment

• Severe renal impairment (creatinine clearance less than 30 ml/minute)


• Known or suspected mechanical GI obstruction


Use cautiously in:

• renal impairment

• severe or persistent diarrhea, known or suspected GI tract lesions

• pregnant or breastfeeding patients

• children (safety and efficacy not established).


• Once drawn into syringe, if drug won't be given immediately, store at ambient room temperature and administer within 24 hours.

Adverse reactions

CNS: dizziness, malaise

GI: nausea, abdominal pain, diarrhea, flatulence abdominal cramping, GI perforation

Other: flushing, pain, diaphoresis



Patient monitoring

Monitor patient for severe or persistent diarrhea and signs and symptoms of GI perforation. Discontinue drug if either occurs.

Patient teaching

• Teach patient who will take drug at home how to prepare and administer it and discard supplies properly.

• Tell patient that if drug won't be administered immediately after it's drawn into syringe, it should be stored at ambient room temperature and administered within 24 hours.

• Inform patient that solution should be clear and colorless to pale yellow.

• Advise patient to stay near toilet facilities after receiving drug.

Instruct patient to stop taking drug if severe or persistent diarrhea or severe, persistent, or worsening abdominal signs or symptoms occur.

• Tell patient that common side effects include transient abdominal pain, nausea, and vomiting. Advise patient to contact prescriber if these symptoms persist or worsen.

• Instruct patient to stop taking drug if opioid pain medication is discontinued.

• As appropriate, review all other significant adverse reactions mentioned above.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved
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References in periodicals archive ?
RELISTOR (methylnaltrexone bromide) tablets, for oral use and RELISTOR (methylnaltrexone bromide) injection, for subcutaneous use
District Court of New Jersey upheld the validity and determined Actavis' infringement of a patent protecting RELISTOR[R] (methylnaltrexone bromide) tablets, expiring March 2031.
Pharmaceutical company Valeant Pharmaceuticals International Inc (NYSE:VRX)(TSX:VRX) reported on Monday an increase in its sales force by nearly 40% to capture untapped primary care OIC market for its key products, Xifaxan (rifaximin) and RELISTOR (methylnaltrexone bromide) with immediate effect.
Relistor (methylnaltrexone bromide) is indicated for treatment of opioid-induced constipation when response to laxative therapy has not been sufficient in adult patients, aged 18 years and older
Methylnaltrexone Bromide. Methylnaltrexone bromide, the first clinically available peripherally acting opioid antagonist, is indicated for OIC in patients receiving palliative care who showed an inadequate response to usual laxative therapy.
TARRYTOWN, N.Y.--The Food and Drug Administration along with the European Medicines Agency (EMA) of the European Union and Health Canada (the Canadian regulatory agency) have each approved single-use, prefilled syringes of Relistor (methylnaltrexone bromide) subcutaneous injection for use in their respective territories.
The European Medicines Agency's Committee for Medicinal Products for Human Use recommended approval of Relistor (methylnaltrexone bromide) in Europe for opioid- constipation in advanced illness patients who are receiving palliative care.
(methylnaltrexone bromide, Wyeth and Progenics Pharmaceuticals Inc.)
The US Food and Drug Administration has approved Relistor (methylnaltrexone bromide) tablets intended to treat opioid-induced constipation in adults with chronic non-cancer pain, it was reported yesterday.
Food and Drug Administration (FDA) requesting approval for the use of RELISTOR(R) (methylnaltrexone bromide) subcutaneous injection for the treatment of opioid-induced constipation (OIC) in patients with chronic, non-cancer pain.