"Young children have died or become seriously ill from accidental exposure to a skin patch containing fentanyl, a powerful pain reliever. As a result of this, the Food and Drug Administration (FDA) is issuing a Drug Safety Communication to warn pa"...
(methylnaltrexone bromide) Subcutaneous Injection
RELISTOR (methylnaltrexone bromide) injection, a peripherally-acting mu-opioid receptor antagonist, is a sterile, clear and colorless to pale yellow aqueous solution. The chemical name for methylnaltrexone bromide is (R)-N-(cyclopropylmethyl) noroxymorphone methobromide. The molecular formula is C21H26NO4Br, and the molecular weight is 436.36.
Each 3 mL vial contains 12 mg of methylnaltrexone bromide in 0.6 mL of water. The excipients are 3.9 mg sodium chloride USP, 0.24 mg edetate calcium disodium USP, and 0.18 mg glycine hydrochloride. During manufacture, the pH may have been adjusted with hydrochloric acid and/or sodium hydroxide.
Each 8 mg/0.4 mL pre-filled syringe (1 mL syringe) contains 8 mg of methylnaltrexone bromide in 0.4 mL of water. The excipients are 2.6 mg sodium chloride USP, 0.16 mg edetate calcium disodium USP, and 0.12 mg glycine hydrochloride.
Each 12 mg/0.6 mL pre-filled syringe (1 mL syringe) contains 12 mg of methylnaltrexone bromide in 0.6 mL of water. The excipients are 3.9 mg sodium chloride USP, 0.24 mg edetate calcium disodium USP, and 0.18 mg glycine hydrochloride.
The structural formula is:
What are the possible side effects of methylnaltrexone (Relistor)?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have severe or ongoing diarrhea, stomach pain that will not go away, black or bloody stools, coughing up blood, or nausea or vomiting that are new or worsening symptoms.
Less serious side effects may include:
- stomach pain, gas;
- mild nausea or diarrhea;
- dizziness; or
- increased sweating.
This is not a complete list of side effects and...
Last reviewed on RxList: 9/19/2013
This monograph has been modified to include the generic and brand name in many instances.
Additional Relistor Information
Report Problems to the Food and Drug Administration
Chronic Pain/Back Pain
Find tips and advances in treatment.