(alvimopan) capsules 12 mg, for oral use


Reduced time to discharge

Adding ENTEREG to an accelerated postoperative care pathway reduced time to discharge by up to 22 hours1

In the ENTEREG clinical trials, the time from end of surgery to discharge order written (DOW) for patients undergoing surgeries that include partial bowel resection with primary anastomosis represented the length of hospital stay.1

DOW was included as a secondary endpoint based on data from 4 multicenter, randomized, double-blind, parallel-group, placebo-controlled studies in patients undergoing bowel resection* and 1 randomized, double-blind, placebo-controlled study in patients undergoing radical cystectomy.

Reduction in Hours to Discharge Order Written for Phase 3 Bowel Resection Studies
Reduction in Hours to Discharge Order Written for Phase 4 Radical Cystectomy Study

Median time to DOW was reduced with use of ENTEREG by 8 hours (Study 1), 6 hours (Study 2), 22 hours (Study 3), and 16 hours (Study 4) in the phase 3 bowel resection studies and 19 hours in the phase 4 radical cystectomy study (Study 6).1 Ns for ENTEREG and placebo groups are for modified ITT.


ENTEREG is indicated to accelerate the time to upper and lower gastrointestinal recovery following surgeries that include partial bowel resection with primary anastomosis.

Selected Safety Information


  • Increased incidence of myocardial infarction was seen in a clinical trial of patients taking alvimopan for long-term use. No increased risk was observed in short-term trials.
  • Because of the potential risk of myocardial infarction, ENTEREG is available only through a restricted program for short-term use (15 doses) called the ENTEREG Access Support and Education (E.A.S.E.) Program.


ENTEREG Capsules are contraindicated in patients who have taken therapeutic doses of opioids for more than 7 consecutive days immediately prior to taking ENTEREG.

Warnings and Precautions

There were more reports of myocardial infarctions in patients treated with alvimopan 0.5 mg twice daily compared with placebo-treated patients in a 12-month study of patients treated with opioids for chronic pain. In this study, the majority of myocardial infarctions occurred between 1 and 4 months after initiation of treatment. This imbalance has not been observed in other studies of alvimopan, including studies of patients undergoing bowel resection surgery who received alvimopan 12 mg twice daily for up to 7 days. A causal relationship with alvimopan has not been established.

E.A.S.E. Program for ENTEREG: ENTEREG is available only to hospitals that enroll in the E.A.S.E. ENTEREG REMS Program. To enroll in the E.A.S.E. Program, the hospital must acknowledge that:

  • Hospital staff who prescribe, dispense, or administer ENTEREG have been provided the educational materials on the need to limit use of ENTEREG to short-term, inpatient use
  • Patients will not receive more than 15 doses of ENTEREG
  • ENTEREG will not be dispensed to patients after they have been discharged from the hospital

ENTEREG should be administered with caution to patients receiving more than 3 doses of an opioid within the week prior to surgery. These patients may be more sensitive to ENTEREG and may experience GI side effects (eg, abdominal pain, nausea and vomiting, diarrhea).

ENTEREG is not recommended for use in patients with severe hepatic impairment, end-stage renal disease, complete gastrointestinal obstruction, or pancreatic or gastric anastomosis, or in patients who have had surgery for correction of complete bowel obstruction.

Adverse Reactions

The most common adverse reaction (incidence ≥1.5%) occurring with a higher frequency than placebo among ENTEREG-treated patients undergoing surgeries that included a bowel resection was dyspepsia (ENTEREG, 1.5%; placebo, 0.8%).

Before prescribing ENTEREG, please read the accompanying Prescribing Information, including the Boxed Warning about potential risk of myocardial infarction with long-term use.


1. Data available on request from Merck & Co Inc., Professional Services-DAP, WP1-27, PO Box 4, West Point, PA 19486-0004. Please specify information package ANES-1149072-0001.