Newer IBS Medications
There are newer medications that have been shown to be effective in treating multiple symptoms of irritable bowel syndrome (IBS) in multi-center, high quality clinical trials. These are prescription medications intended for specific use under a doctor’s supervision.
IBS with Diarrhea (IBS-D)
Alosetron (Lotronex) blocks serotonin signals that transmit sensory information (painful and nonpainful) from the gut to the brain and helps to reduce diarrhea and abdominal pain. Alosetron has been approved for the use in women with severe diarrhea-predominant IBS (IBS-D). It is prescribed under a Risk Management Program requiring careful monitoring and education due to rare but potentially serious side effects.
Rifaximin (Xifaxan) is an antibiotic approved in May 2015 by the U.S. Food and Drug Administration (FDA) for treatment of IBS with diarrhea (IBS-D) in adults. It works by reducing or altering bacteria in the gut. It has been found to improve IBS symptoms of bloating and diarrhea after a 10–14 day course of treatment. It is only slightly absorbed in the gut and is generally tolerated well. Although some patients experience relief of IBS symptoms after taking a course of rifaximin, others require retreatment. More information is needed about the duration of symptom relief and the best management approach to prevent recurrence of symptoms or if symptoms recur.
Eluxadoline (Viberzi) is a new drug which activates receptors in the nervous system that can lessen bowel contractions. It is prescribed for the treatment of IBS with diarrhea (IBS-D) in adult men and women. In studies, eluxadoline was shown to reduce abdominal pain and improve stool consistency. The drug was FDA approved in May 2015, with the recommendation it be classified as a controlled substance. Product availability is expected in early 2016.
IBS with Constipation (IBS-C)
Lubiprostone (Amitiza) helps to promote secretion through chloride channels in the bowel which in turn promote peristalsis, the coordinated muscle contractions that propel contents through the gastrointestinal (GI) tract. This medication has been shown to be effective for treating constipation symptoms. It is approved for use in women with constipation-predominant IBS (IBS-C), and in men and women with chronic constipation (without predominant abdominal pain).
Linaclotide (Linzess) is in a class of medications called guanylate cyclase-C agonists. It works by increasing the movement of contents through the GI tract and by blocking pain signals in the intestines. The medication is prescribed in adults aged 18 and older for IBS with constipation (IBS-C) and for chronic constipation (CC). In studies, patients taking linaclotide experienced improvement in multiple symptoms including pain or discomfort, bloating, and bowel function. Linaclotide is available in Canada and Europe under the brand name Constella.
Drugs Being Studied
Research is ongoing to find new medication treatment choices for people with IBS.
Probiotics are microorganisms that are beneficial to health. They are usually live bacteria. Some evidence supports a role in IBS for specific probiotic supplement formulations, mainly for symptoms of gas and bloating.
New prescription drugs are currently being studied. These have not yet been FDA approved for the treatment of IBS. Drugs for treatment of IBS with constipation currently in Phase 3 clinical trials include plecanatide, and a first-in-class compound, elobixibat.
Adapted IFFGD Publication #101 revised and updated by Douglas A. Drossman, MD, Drossman Gastroenterology PLLC, Chapel Hill, NC and IFFGD Publication #168 by Tony Lembo, MD and Rebecca Rink, MS, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Boston, MA.