RELISTOR Prefilled Syringe

The RELISTOR prefilled syringe is available in 2 fixed doses and is ready to use.

The following instructions explain how to prepare and give an injection of RELISTOR the right way when using a prefilled syringe of RELISTOR.

The pre-filled syringe is not appropriate for all patients. These directions should only be used if your physician has prescribed the 8 mg or 12 mg
pre-filled syringe. Please refer to the Prescribing Information and Med Guide for full instructions on how to administer RELISTOR.

Patient instructions for use

Before starting, read and make sure you understand the Patient Instructions for Use. If you have any questions, talk to your healthcare provider.

Gather the supplies you will need for your injection. These include

  1. RELISTOR prefilled syringe
  2. Alcohol swab
  3. Cotton ball or gauze
  4. Adhesive bandage
  5. Container to dispose of used pre-filled syringes and needles.See Step 4:"Dispose of used pre-filled syringes and needles."

Important notes

  • Do not use a RELISTOR prefilled syringe more than one time, even if there is medicine left in the syringe
  • Safely throw away RELISTOR prefilled syringes after use (see step 4)
  • To avoid needle-stick injuries, do not recap used needles
  • Image showing the Trigger Fingers on a Relistor prefilled syringeAvoid touching the trigger fingers of the RELISTOR prefilled syringe to keep from activating the safety device too soon. The safety device (needle guard) is activated by pressure from the plunger on the trigger fingers
  • Store RELISTOR pre-filled syringes at room temperature between 68°F to 77°F (20°C to 25°C). Do not freeze RELISTOR. Keep RELISTOR away from light until you are ready to use it. For more information about how to store RELISTOR, see the section called "How should I store RELISTOR?" in the Instructions for Use
Choosing and preparing an injection site
  1. Subcutaneous injection sites on the abdomen, thighs, and armsChoose an injection site—abdomen, thighs, or upper arms. See shaded areas in the figure. Do not inject at the exact same spot each time (rotate injection sites). Do not inject into areas where the skin is tender, bruised, red, or hard. Avoid areas with scars or stretch marks.
    Abdomen or thigh—use these sites when injecting yourself or another person.
    Upper arm—use this site only when injecting another person.
  2. Picture showing how to apply pressure to the injection site with a cotton ballClean the injection site with an alcohol swab and let it air-dry. Do not touch this area again before giving the injection.
Preparing the injection for prefilled syringe
  1. Find a quiet place. Choose a flat, clean, well-lit working surface.
  2. Wash your hands with soap and warm water before preparing for the injection.
  3. Picture of a prefilled syringe showing a yellow plunger rod for 8mg dose and dark blue rod for 12 mg doseLook at the prefilled syringe of RELISTOR. Make sure that the dose prescribed by your healthcare provider matches the dose on the prefilled syringe label. Look at the plunger rod of the syringe. If the dose prescribed by your healthcare provider is 8 mg, the plunger rod will be yellow; if the prescribed dose is 12 mg, the plunger rod of the syringe will be dark blue.
  4. The liquid in the prefilled syringe should be clear and colorless to pale yellow and should not have any particles in it. If not, do not use the prefilled syringe, and call your healthcare provider.
  5. Picture showing how to safely remove the needle cap on a prefilled syringeFirmly hold the barrel of the prefilled syringe and pull the needle cap straight off. Do not touch the needle or allow it to touch any surface.
Injecting RELISTOR
  1. Picture showing how to pinch a fold of skin around the injection sitePinch the skin around the injection site.
  2. Image of syringe injection into the skin at  a 45-degree angleInsert the full length of the needle into the skin at a 45-degree angle with a quick "dart-like" motion.

    Let go of the skin and slowly push down on the plunger with your thumb until the prefilled syringe is empty. This will release the needle safety device.
    Image showing how to push the syringe plunger until the syringe is empty
  3. Picture demonstrating how to remove your thumb from the syringe plunger to activate the protective sleeve for the needleContinue to hold pressure on the plunger with your thumb and quickly pull the needle out of the skin. Be careful to keep the needle at the same angle as it was inserted. Then remove your thumb from the plunger to allow the protective sleeve to cover the needle. There may be a little bleeding at the injection site.
  4. Picture showing how to apply pressure to the injection site with a cotton ballHold a cotton ball or gauze over the injection site. Do not rub the injection site. Apply an adhesive bandage to the injection site if needed.
Disposing of supplies
  1. Do not reuse the prefilled syringe or recap the needle. Place the used prefilled syringe in a closeable, puncture-resistant container. You may use a sharps container (such as a red biohazard container), a hard plastic container (such as a detergent bottle), or a metal container (such as an empty coffee can). Ask your healthcare provider for instructions on the right way to throw away (dispose of) the container. There may be state and local laws about how you should throw away used needles and syringes.
  2. If you have any questions, talk to your healthcare provider or pharmacist.


RELISTOR® is a prescription medicine used to treat constipation that is caused by prescription pain medicines called opioids, in adults:

  • with long-lasting (chronic) pain that is not caused by cancer.
  • receiving treatment for advanced illness, when other medicines for constipation have not worked well enough.
    • It is not known if RELISTOR is safe and effective if used for longer than 4 months in people with advanced illness.

Important Safety Information

Do not take RELISTOR® (methylnaltrexone bromide) Subcutaneous Injection if you have or may have a blockage in your intestines (called an intestinal obstruction) or a history of bowel blockage.

RELISTOR can cause serious side effects such as a tear in your stomach or intestinal wall (perforation). Stomach pain that is severe can be a sign of a serious medical condition. If you get stomach pain that does not go away, stop taking RELISTOR and get emergency medical help right away.

Stop using RELISTOR and call your healthcare provider if you get diarrhea that is severe or that does not go away during treatment with RELISTOR.

You may have symptoms of opioid withdrawal during treatment with RELISTOR including sweating, chills, diarrhea, stomach pain, anxiety, and yawning. Tell your healthcare provider if you have any of these symptoms.

Tell your healthcare provider if you have kidney problems or if you have any stomach or bowel (intestines) problems, including stomach ulcer, Crohn’s disease, diverticulitis, cancer of the stomach or bowel, or Ogilvie’s syndrome. Also, tell your healthcare provider about all of the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Tell your healthcare provider if you are pregnant or plan to become pregnant. Taking RELISTOR during pregnancy may cause opioid withdrawal symptoms in your unborn baby. Tell your healthcare provider right away if you become pregnant during treatment with RELISTOR. It is not known if RELISTOR passes into your breast milk. Taking RELISTOR while you are breastfeeding may cause opioid withdrawal in your baby. You and your healthcare provider should decide if you will take RELISTOR or breastfeed. You should not do both.

The most common side effects of RELISTOR in people with long-lasting (chronic) pain that is not caused by cancer include: stomach-area (abdomen) pain, nausea, diarrhea, sweating, hot flush, tremor, and chills.

The most common side effects of RELISTOR in people receiving treatment for their advanced illness include: stomach-area (abdomen) pain, gas, nausea, dizziness, and diarrhea.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088.

For product information, adverse event reports, and product complaint reports, please contact:

Salix Product Information Call Center
Phone: 1-800-508-0024
Fax: 1-510-595-8183

Click here for full Prescribing Information.

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