Recommended Relistor Injection Sites
Relistor (methylnaltrexone bromide) is a subcutaneous injection, meaning it is administered into the fatty tissue just below the skin. The recommended areas for injection are the abdomen, thighs, and, for injections given by another person, the upper arms. Using these sites and rotating between them helps ensure consistent medication absorption and reduces the risk of skin irritation or tissue damage over time.
The Abdomen
The abdominal area is a common and often preferred site for self-injection because it typically has a good layer of fatty tissue and is easy to reach. To inject in the abdomen, you should use the area between the ribcage and the hip bones, at least two inches away from the navel. It is best to alternate sides of the abdomen with each injection to follow the rotation guideline.
The Thighs
The thighs are another excellent site for self-injection, providing a large surface area for rotation. The recommended area is the front and outer area of the thigh, midway between the hip and the knee. Like the abdomen, it is important to rotate between the left and right thigh with each dose.
The Upper Arms
For many, especially those who inject themselves, the upper arms are more challenging to reach for a proper injection. For this reason, the upper arm is typically reserved for injections administered by a caregiver or healthcare provider. The proper injection zone is the fatty tissue on the back or side of the upper arm. If a caregiver is administering the injection, they should alternate between the left and right upper arm as part of the rotation schedule.
The Importance of Rotating Injection Sites
Rotating injection sites is a critical part of a safe and effective treatment plan with Relistor. Failure to rotate can lead to a number of adverse skin reactions and issues. Here's why it's so important:
- Prevents tissue damage: Repeated injections in the same small area can lead to lipodystrophy, a condition characterized by a breakdown of fat cells or the formation of fatty lumps, which can affect medication absorption.
- Reduces pain and bruising: Giving the skin time to heal between injections at the same spot minimizes discomfort and the likelihood of bruising, tenderness, or redness.
- Maintains consistent absorption: Proper rotation helps ensure the medication is absorbed consistently, maximizing its effectiveness. The rate and consistency of absorption can be altered if the medication is injected into scarred or damaged tissue.
- Ensures hygiene: Rotating sites encourages a fresh, clean injection site each time, reducing the risk of infection.
To effectively rotate, you can imagine dividing each injection area (abdomen, thigh) into quadrants and moving from one quadrant to the next with each dose. Keeping a log or mental map of your rotation schedule is a good practice to ensure consistency.
Areas to Avoid When Injecting Relistor
Just as important as knowing where to inject is knowing which areas to avoid. Injecting into unsuitable sites can cause pain, increase the risk of bruising, and negatively affect the medication's absorption. Specifically, avoid injecting into any area that is:
- Bruised, red, or tender: These are signs of inflammation or recent trauma, and injection here would be more painful and less effective.
- Hard or lumpy: These could indicate underlying scar tissue or lipodystrophy from previous injections.
- Scarred or has stretch marks: Scarred tissue can interfere with the medication's absorption.
- Near the navel: Stay at least two inches away from the belly button when injecting in the abdomen.
Relistor Injection Site Comparison
| Injection Site | Ease of Self-Injection | Visibility of Site | Absorption Characteristics | Pain/Discomfort Level |
|---|---|---|---|---|
| Abdomen | Excellent: Large, easily accessible area with ample fatty tissue. | Low: Less visible to others under clothing. | Excellent: Generally consistent and quick absorption due to good blood supply in the fatty layer. | Low: Minimal nerve endings in the fatty layer. |
| Thigh | Good: Accessible for self-injection, especially the front and outer areas. | Low: Easily covered with clothing. | Good: Consistent absorption; may have fewer fatty tissue layers than the abdomen for some individuals. | Low to Moderate: Depends on the fat layer; may be slightly more sensitive than the abdomen. |
| Upper Arm | Poor (Self-Injection): Difficult to access and stabilize for a proper self-injection technique. | High: More visible, requiring discretion if injecting publicly. | Good: Consistent absorption; typically performed by a caregiver. | Moderate: May be more muscular and sensitive for some patients. |
General Injection Technique
Regardless of the injection site, the basic procedure for a subcutaneous injection remains the same:
- Preparation: Gather all necessary supplies: the Relistor pre-filled syringe or vial, alcohol swab, cotton ball, and a sharps disposal container.
- Inspect: Check the medication for any discoloration or particles. Relistor should be clear and colorless to pale yellow.
- Select a site: Choose a new, clean injection site from one of the recommended areas.
- Clean the site: Use an alcohol swab to clean the chosen area and let it air dry completely.
- Pinch the skin: Gently pinch a fold of skin and fatty tissue between your thumb and forefinger.
- Inject: Hold the syringe like a dart and quickly insert the needle into the pinched skin at a 45-degree angle (or 90-degree angle for thicker tissue).
- Administer: Slowly push the plunger to inject all the medication.
- Withdraw: Pull the needle straight out and release the skin fold.
- Post-injection: Gently press a cotton ball over the injection site. Do not rub the area.
- Dispose: Immediately place the used syringe into a sharps container.
For more detailed instructions, always refer to the full prescribing information provided with your medication, such as the resources found at the manufacturer's website. [^1]
Conclusion
For Relistor subcutaneous injections, the abdomen, thighs, and upper arms offer safe and effective sites for administration. The most critical practice, regardless of the chosen site, is the rotation of injection locations with every dose. This helps prevent tissue damage, reduces discomfort, and ensures that the medication is absorbed consistently and effectively. By following these best practices and avoiding unsuitable injection areas, patients can minimize side effects and optimize their treatment with Relistor.
[^1]: Relistor.com. (n.d.). Instructions for Use. Retrieved October 5, 2025, from https://www.relistor.com/opioid-induced-constipation-faqs
