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Relistor SubQ Precautions and Side Effects


IMPORTANT NOTE: The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate or effective for you. Consult your healthcare professional before using this drug.

Table of Contents

Generic Name: METHYLNALTREXONE - INJECTION
Pronounced: (METH-il-nal-TREX-one)

Relistor SubQ Precautions

Before using methylnaltrexone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:

  • stomach/bowel blockage (gastrointestinal obstruction)

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

  • kidney disease
  • stomach/intestinal ulcers or tumors

This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

To lower your risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

Before having surgery, tell your doctor or dentist that you are using this medication.

During pregnancy, this medication should be used only when clearly needed.

It is not known if this medication passes into breast milk. Consult your doctor before breast-feeding.

Relistor SubQ Side Effects

Stomach/abdominal pain, nausea, gas, dizziness, fever, or diarrhea may occur. Pain, redness, or swelling at the injection site may also occur. If any of these effects persist or worsen, tell your doctor or pharmacist immediately.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Stop using methylnaltrexone and tell your doctor right away if any of these rare but very serious effects occur:

  • severe, persistent or worsening stomach/abdominal pain
  • fever

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any of the following symptoms of a serious allergic reaction:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.



CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.
Information last revised October 2011 Copyright(c) 2011 First DataBank, Inc.