Viberzi for IBS

Customers and female pharmacist in a pharmacy

What Is Viberzi?

Viberzi (eluxadoline) is a medication that has received FDA approval for the treatment of diarrhea-predominant IBS (IBS-D) in adults. In Europe, the medication is known as Truberzi. Viberzi was designed to act locally on the digestive system so as to reduce abdominal pain and diarrhea.

How Does Viberzi Work?

Viberzi works by affecting opioid receptors within the digestive tract. These specific receptors are involved in gut motility, pain sensation, and secretion of liquid.

Viberzi has a mixed action on three different receptor types - it activates two of them and inhibits one of them so as to get the desired relief of IBS-D symptoms, but without causing constipation.

If you are a science geek, the specific actions of Viberzi are:

  • Mu receptor agonist
  • Delta receptor antagonist
  • Kappa receptor agonist

The thinking behind Viberzi seems to be that by adding in the delta antagonist, you avoid the constipating effect seen in Imodium and Lomotil, which are only u-opoid agonists.

Research indicates that Viberzi works locally on the digestive tract, with very little systemic effects.

How Do You Take Viberzi?

Take the medication as directed by your doctor. It is designed to be taken by mouth, twice a day, with a meal.

Viberzi is considered a "controlled substance" because it runs the risk of substance abuse. 

How Effective is Viberzi for IBS?

The FDA approved Viberzi based on the results of two Phase III clinical trials.

According to the FDA, these trials showed that Viberzi was superior to placebo in "reducing abdominal pain and improving stool consistency", over a 26 week treatment period. It is important to note that these studies have not yet been published.

A Phase II clinical trial, with a smaller study population, found "modest" improvement on symptoms such as frequency and urgency of bowel movements, as well as "modest" improvement in overall symptoms and adequate symptom relief.

Side Effects of Viberzi

According to the FDA, side effects of Viberzi are typically gastrointestinal in nature, including abdominal pain, constipation and nausea. A more significant risk has to do with the medication's effect on the sphincer of Oddi, which can lead to pancreatitis.

According to the press release from the drug's manufacturer, a small percentage of people in the Phase III trials experienced constipation and nausea. Two percent of individuals in both the Viberzi and placebo groups dropped out of the trial due to constipation. Less than 1% of participants reported experiencing severe constipation.

In the Phase II study, a higher dosage of the medication (200 mg) led to an increase in side effects, all gastrointestinal in nature. The most severe of these was the report of a few cases of pancreatitis. In the larger Phase III trial, dosage was limited to 75 and 100 mg.

Because Viberzi is an opiate, there are some concerns regarding a potential for abuse and/or dependence as was seen in some animal studies of the medication.

Who Should Not Use Viberzi?

According to the FDA, you should not use Viberzi if you have a history of any of the following:

  • Severe constipation
  • Severe liver impairment

The FDA also states that you should not use Viberzi if you drink more than three alcoholic drinks a day.

Based on the Phase II trial, you should not use Viberzi if you have a history of sphincter of Oddi dysfunction  - a condition you might be at higher risk for if you have had your gallbladder removed


"Actavis Receives FDA Approval for VIBERZI (eluxadoline) for the Treatment of Irritable Bowel Syndrome with Diarrhea (IBS-D) in Adults" Press Release May 27, 2015.

Davenport, J., "Effect of uptake transporters OAT3 and OATP1B1 and efflux transporter MRP2 on the pharmacokinetics of eluxadoline" Journal of Clinical Pharmacology 2015 55:534-542.

Dove, L., "Eluxadoline Benefits Patients With Irritable Bowel Syndrome With Diarrhea in a Phase 2 Study" Gastroenterology 2013 145:329-338.

"FDA approves two therapies to treat IBS-D" U.S. Food and Drug Administration Website May 27, 2015.

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