Relistor (Methylnaltrexone)

Description

Relistor (Methylnaltrexone) is a medication that is part of a group of drugs called opioid antagonists. It works by blocking the opioid receptors in the intestines, which helps alleviate constipation caused by opioid pain medications. This drug is specifically developed for people experiencing constipation due to long-term opioid use for pain management, including those with chronic non-cancer pain and those with cancer who no longer require weekly increases in opioid dosage.

Directions

The suggested dose for Relistor injections in adults living with chronic non-cancer pain-related constipation is a single 12 mg daily dose. For adults with advanced illness accompanied by opioid-induced constipation, the dosage varies depending on weight: For those under 38 kg, a daily dosage of 0.15 mg/kg is recommended; for individuals weighing from 38 kg up to 62 kg, an 8 mg daily dose is recommended; for those between 62 kg and 114 kg, the suggested dose is 12 mg daily; and for those more than 114 kg, a daily dosage of 0.15 mg/kg is prescribed.

Always follow the instructions provided by your medical professional and seek further clarification if needed. Before administering the injection, ensure the targeted skin area is both clean and visibly free from infection. Injections can be administered into the thigh, upper arm, or abdominal region.

Ingredients

The active ingredient in Relistor is methylnaltrexone bromide.

Contraindications

Avoid taking or using Relistor if any of the following apply:

• Known hypersensitivity to methylnaltrexone or any of its components
• Gastrointestinal obstruction or blockage

Cautions

• Before taking Relistor, it is important to inform your doctor about:
• Any medications you take, to prevent possible interactions
• Any medical conditions you have, such as liver or kidney disease which might require a dosage adjustment
• If you are pregnant or breastfeeding
• If you plan to become pregnant or breastfeed

• Exercise caution if you're already aware of or suspect gastrointestinal issues; the use of Relistor could pose risks. In case of persistent or worsening stomach pain, discontinue the medication and seek immediate medical help.
• In instances of ongoing or severe diarrhea while on this medication, discontinuation of Relistor and consultation with your healthcare provider is recommended.
• For those with a compromised blood-brain barrier, weigh the pros and cons before using Relistor with a healthcare provider. Watch for signs of opioid withdrawal, including restlessness, nausea, or anxiousness, and reach out to your healthcare provider if needed.
• Ensure you have easy access to a bathroom facility when taking the medication.
• Stop taking Relistor if your healthcare provider discontinues opioid pain treatment.
• If your history of opioid use is less than a month, you may find the effectiveness of Relistor to be reduced.
• Before starting Relistor, it is advised to stop any regular laxative use. If Relistor doesn't provide the expected results within three days, you may consider restarting laxative use.
• Should your opioid medication regimen change, reconsider the need for ongoing Relistor use with a healthcare provider.
• Routine healthcare provider check-ups are recommended to monitor the drug’s efficacy and possible adverse effects.

Side Effects

While Relistor can provide relief for patients, there are certain side effects that individuals should be aware of before beginning treatment. The most common side effects of Relistor include:

• Diarrhea
• Headache
• Sweating
• Anxiety
• Muscle spasms
• Pain in the stomach area
• Chills
• Runny nose

Relistor may also cause severe side effects, including:

• Digestive Tract Complications: Severe pain in the abdominal area may be a sign of a serious issue like a gastrointestinal perforation. If you experience persistent or escalating severe stomach pain, discontinue the medication and seek immediate medical attention.
• Persistent or Intense Diarrhea: If you experience persistent or severe diarrhea, it's important to stop using Relistor and consult a healthcare professional.
• Symptoms of Opioid Withdrawal: While on this medication, you may experience withdrawal symptoms like excessive sweating, diarrhea, abdominal pain, nervousness, and chills. If you experience any of these symptoms, contact your healthcare provider.

This is not an exhaustive list of side effects. If you experience any side effects, consult a healthcare provider for proper advice and management.

References:

1. Relistor (Methylnaltrexone) Prescribing Information. Bridgewater, NJ: Salix Pharmaceuticals; 2018.

About Dr. Gerardo Sison (Page Author)

An honors graduate of the University of Florida, Dr. Sison started his pharmacy career in a community setting, extending his services to hospitals and clinics over time. He has also worked in medication therapy management, advising patients on proper medication use for their chronic health conditions. Read More....