Relistor Side Effects
Generic name: methylnaltrexone
Medically reviewed by Drugs.com. Last updated on Aug 9, 2023.
Note: This document contains side effect information about methylnaltrexone. Some dosage forms listed on this page may not apply to the brand name Relistor.
Applies to methylnaltrexone: subcutaneous solution. Other dosage forms:
Serious side effects of Relistor
Along with its needed effects, methylnaltrexone (the active ingredient contained in Relistor) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur while taking methylnaltrexone:
More common
- Diarrhea
- increased sweating
Incidence not known
- Bloody, black, or tarry stools
- heartburn
- indigestion
- nausea
- severe abdominal or stomach pain, cramping, or burning
- trouble breathing
- vomiting of material that looks like coffee grounds, severe and continuous
Get emergency help immediately if any of the following symptoms of overdose occur while taking methylnaltrexone:
Symptoms of overdose
- Chills
- cold sweats
- confusion
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
Other side effects of Relistor
Some side effects of methylnaltrexone may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.
Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
- Bloated
- dizziness
- excess air or gas in the stomach or intestines
- feeling of fullness
- passing of gas
- stomach pain
For Healthcare Professionals
Applies to methylnaltrexone: oral tablet, subcutaneous kit, subcutaneous solution.
Gastrointestinal
Very common (10% or more): Abdominal pain (up to 29%), flatulence (up to 13%), nausea (up to 12%)
Common (1% to 10%): Diarrhea,
Postmarketing reports: Perforation, cramping, vomiting[Ref]
Nervous system
Common (1% to 10%): Dizziness, tremor[Ref]
Dermatologic
Common (1% to 10%): Hyperhidrosis, flushing[Ref]
Other
Common (1% to 10%): Chills
Postmarketing reports: Malaise, pain, cases of opioid withdrawal[Ref]
Cardiovascular
In an open-label, uncontrolled study (n=1034), 4 myocardial infarctions (1 fatal), 1 stroke (fatal), 1 fatal cardiac arrest, and 1 sudden death were reported. It is not possible to establish a relationship between these events and use of this drug.[Ref]
Frequency not reported: Myocardial infarctions[Ref]
General
The most common adverse reactions included abdominal pain, nausea, diarrhea, hyperhidrosis, hot flush, tremor, and chills.[Ref]
Local
Common (1% to 10%): Injection site reactions including stinging, burning, pain, redness, and edema[Ref]
Frequently asked questions
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Patient resources
- Relistor drug information
- Relistor (Methylnaltrexone Subcutaneous) (Advanced Reading)
- Relistor (Methylnaltrexone bromide Oral) (Advanced Reading)
- Relistor (Methylnaltrexone Tablets)
Professional resources
Related treatment guides
References
1. Cerner Multum, Inc. UK Summary of Product Characteristics.
2. Cerner Multum, Inc. Australian Product Information.
3. Product Information. Relistor (methylnaltrexone). Wyeth Laboratories. 2008.
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.