Talk with your doctor about the method that's best for you

The prefilled syringe comes already filled with the dose prescribed by your doctor, so you don't have to worry whether you've put the right amount of RELISTOR into it.

No matter how you take RELISTOR, it is injected just under the skin (a subcutaneous injection); it is not a "deep" or intramuscular (into the muscle) injection.

  • Prefilled syringe

    Picture of a prefilled syringe showing a yellow plunger rod for 8mg dose and dark blue rod for 12mg dose A syringe that comes prefilled with the dose prescribed by your healthcare provider. The prefilled syringe is color-coded, with a yellow plunger rod for an 8-mg dose and a dark blue plunger rod for a 12-mg dose.

    How to use a prefilled syringe

Here are some general questions that patients often ask about RELISTOR.1

For detailed, step-by-step instructions on how to inject RELISTOR, please click on one of the links above that matches the type of syringe that you will be using.

How should I take RELISTOR?
Subcutaneous injection sites on the abdomen, thighs, and arms
  • Take RELISTOR exactly as your healthcare provider tells you


  • Take RELISTOR by an injection under the skin (subcutaneous injection) of the upper arm, abdomen, or thigh

How often?

  • The usual dose schedule is once every other day, as needed, but not more than once in a 24-hour period

If you stop taking your prescription pain medicine, check with your healthcare provider before continuing RELISTOR. Also, if you take more RELISTOR than prescribed, talk to your healthcare provider right away.

Who should not take RELISTOR?

Do not take RELISTOR if you have or may have a blockage in your intestines called a mechanical bowel obstruction. Symptoms of this blockage are vomiting, stomach pain, and swelling of your abdomen. Talk to your healthcare provider before taking RELISTOR if you have any of these symptoms.

What should I tell my healthcare provider before taking RELISTOR?

Tell your healthcare provider about all of your medical conditions, including if you

  • Are pregnant or plan to become pregnant. It is not known if RELISTOR can harm your unborn baby. If you become pregnant while using RELISTOR, tell your healthcare provider right away
  • Are breast-feeding or plan to breast-feed. It is not known if RELISTOR passes into your breast milk
  • Have kidney problems
How should I store RELISTOR?
  • Store RELISTOR vials or prefilled syringes at 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
  • If RELISTOR has been drawn into a syringe and you are unable to use the medicine right away, keep the syringe at room temperature for up to 24 hours. The syringe does not need to be kept away from light during the 24-hour period

Reference: 1. RELISTOR® (methylnaltrexone bromide) Prescribing Information, Salix Pharmaceuticals, Inc; 2012.