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Medications and Drugs

Brand Names: Entereg

Generic Name: alvimopan (Pronunciation: AL vi MOE pan)

What is alvimopan (Entereg)?

Alvimopan reduces certain side effects of narcotic medications that are often used to prevent pain caused by surgery.

Narcotic medications can cause stomach pain, bloating, nausea, vomiting, and constipation. These side effects can delay recovery in patients undergoing gastrointestinal surgery.

Alvimopan works by preventing these side effects without reducing the pain-relieving effects of the narcotic.

Alvimopan is used to speed recovery of stomach and intestinal functions after a gastrointestinal surgery, and to prevent side effects caused by narcotic medications.

Alvimopan may also be used for other purposes not listed in this medication guide.

What are the possible side effects of alvimopan (Entereg)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers at once if you have a serious side effect such as:

  • pale skin, feeling light-headed or short of breath, rapid heart rate, trouble concentrating;
  • painful or difficult urination;
  • urinating less than usual or not at all;
  • confusion, uneven heart rate, extreme thirst, increased urination, leg discomfort, muscle weakness or limp feeling; or
  • chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling.

Less serious side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about alvimopan (Entereg)?

You should not use this medication if you are allergic to alvimopan, if you have severe liver or kidney disease, or if you have used a narcotic medication within the past 7 days. Narcotic medications are used for moderate to severe pain. Some prescription cough medications also contain narcotics.

Before you receive alvimopan, tell your doctor if you have liver or kidney disease.

Alvimopan is given only in a hospital for a short period of time.

Tell your caregivers right away if you have pale skin, easy bruising or bleeding, painful or difficult urination, or confusion with uneven heart rate, leg discomfort, muscle weakness or limp feeling, and increased urination.

Report Problems to the Food and Drug Administration

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

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