Generic Name: methylnaltrexone (METH-il-nal-TREX-one)
Brand Name: Relistor
Methylnaltrexone is used for:
Treating constipation caused by opioid medicines in certain patients. It may also be used for other conditions as determined by your doctor.
Methylnaltrexone is a mu-opioid receptor antagonist. It works by decreasing the effect of opioid medicines in the stomach and bowel, which helps to decrease constipation.
Do NOT use methylnaltrexone if:
- you are allergic to any ingredient in methylnaltrexone
- you have known or suspected stomach or bowel blockage
- you have a history of bowel blockage
Contact your doctor or health care provider right away if any of these apply to you.
Before using methylnaltrexone:
Some medical conditions may interact with methylnaltrexone. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have a history of kidney problems or you are on dialysis
- if you have nausea, vomiting, stomach pain or swelling, or other stomach or bowel problems (eg, cancer, ulcer, Ogilvie syndrome)
- if you have a peritoneal (abdominal) catheter
Some MEDICINES MAY INTERACT with methylnaltrexone. However, no specific interactions with methylnaltrexone are known at this time.
Ask your health care provider if methylnaltrexone may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use methylnaltrexone:
Use methylnaltrexone as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- An extra patient leaflet is available with methylnaltrexone. Talk to your pharmacist if you have questions about this information.
- Methylnaltrexone is given as an injection under the skin. A health care provider will teach you how to use it. Be sure you understand how to use methylnaltrexone. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.
- Methylnaltrexone is colorless to pale yellow in color. Do not use methylnaltrexone if it contains particles, is cloudy or discolored, or if the vial is cracked or damaged.
- If you are using the single-use vials, inject methylnaltrexone right after you draw it into the syringe. If you are not able to inject the medicine right away, it may be stored in the syringe at room temperature for up to 24 hours. You do not need to protect the syringe from light during this time.
- If you are using the prefilled syringes, do not remove the syringe from the tray until you are ready to inject methylnaltrexone.
- Methylnaltrexone may be injected into the upper arm, abdomen, or thigh. Do NOT inject methylnaltrexone into the upper arm if you are injecting yourself.
- Rotate injection sites as directed by your health care provider. Do not inject into scars, stretch marks, or areas where the skin is bruised, tender, red, or hard.
- Do not use a vial of methylnaltrexone more than 1 time, even if there is medicine left in the vial.
- Keep this product, as well as syringes and needles, out of the reach of children and away from pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.
- Use methylnaltrexone as your doctor has told you. If you miss a dose of methylnaltrexone and you take it on a regular basis, use it as soon as you remember. Continue to use it as directed by your doctor.
Ask your health care provider any questions you may have about how to use methylnaltrexone.
Important safety information:
- Tell your doctor or dentist that you take methylnaltrexone before you receive any medical or dental care, emergency care, or surgery.
- Do NOT use more than the recommended dose or use for longer than you were told without checking with your doctor.
- Talk with your doctor before using a laxative with methylnaltrexone.
- Be sure to stay close to a restroom once you have injected methylnaltrexone. Most patients have a bowel movement within a few minutes to a few hours after they use it.
- Methylnaltrexone should only be used by patients who take opioid pain medicines. Tell your doctor if you stop taking your opioid pain medicine.
- Tears in the stomach or bowel (perforation) have happened with methylnaltrexone. Tell your doctor right away if you have severe, worsening, or persistent stomach swelling or pain; severe or persistent nausea or vomiting; black, sticky stools; or bloody vomit.
- Symptoms of opioid withdrawal have happened with methylnaltrexone. Call your doctor right away if you have increased sweating, chills, unusual diarrhea or stomach pain, anxiety, or yawning.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using methylnaltrexone while you are pregnant. It is not known if this medicine is found in breast milk. If you are or will be breast-feeding while you use methylnaltrexone, check with your doctor. Discuss any possible risks to your baby.
Possible side effects of methylnaltrexone:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Dizziness; gas; hot flush; mild diarrhea; nausea; stomach pain; sweating.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); black, tarry stools; bloody vomit; fever or chills; new or worsening nausea or vomiting; severe, persistent, or worsening diarrhea, nausea, vomiting, or stomach pain; tremor.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.Proper storage of methylnaltrexone:
Store methylnaltrexone at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Do not freeze. Store away from heat, moisture, and light. Do not store in the bathroom. Keep methylnaltrexone out of the reach of children and away from pets.
- If you have any questions about methylnaltrexone, please talk with your doctor, pharmacist, or other health care provider.
- Methylnaltrexone is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take methylnaltrexone or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about methylnaltrexone. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to methylnaltrexone. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using methylnaltrexone.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.
More about methylnaltrexone
- Methylnaltrexone oral/injection
- Methylnaltrexone Subcutaneous (Advanced Reading)
- Methylnaltrexone bromide (Advanced Reading)
- Other brands: Relistor