Drug information provided by: Micromedex

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to use it.

This medicine may cause a tear (perforation) in your stomach or bowels. Check with your doctor right away if you have a severe stomach pain that does not go away.

If severe or persistent (non-stop) diarrhea occurs while using methylnaltrexone injection, check with your doctor right away.

Do not suddenly stop using this medicine without checking first with your doctor. Doing so may cause symptoms, such as anxiety, chills, diarrhea, irritability, stomach pain, sweating, and yawning.