Researcher Sorts Through Sea of IBS Remedies

As irritable bowel syndrome (IBS) remains a complicated condition to treat with an etiology that’s still unknown, it’s difficult for physicians to find the best proven therapies among new remedies and the variety of pharmacological and nondrug options they have been trying for years.

At Digestive Disease Week 2013, held May 18-21, 2013, in Orlando, Fla., Brennan Spiegel, MD, MSHS, associate professor of medicine and director of the UCLA/VA Center for Outcomes Research and Education, in Los Angeles, described the range of therapies and evidence supporting everything from peppermint oil and relaxation breathing to the recently approved pharmaceutical linaclotide.

Spiegel began his session by reminding participants not to dismiss the brain-gut access.

“We all have gut feelings that keep us away from danger, but for some patients, there is always a threat in their environment,” he said. “Stress can lead to chronic abdominal pain and other symptoms.”

However, a wide range of mechanisms play a crucial role in IBS, and new research continues to shape its etiology and appropriate treatments. Spiegel said infections such as post-diverticulitis IBS and leaky gut with an inflammatory cascade have gained prominence, and while visceral hypersensitivity and pain and dysmotility support an older concept, they are still possibilities.

Since some patients are more brain than gut — and others are more gut than brain — Spiegel recommended clinicians to begin the treatment process by speaking with the patient to learn about his or her principal concerns and cognitive and emotional issues.

“Then, use that to determine what treatment,” Spiegel said. “Think about symptoms first.”

Relief of pain is usually a prominent goal. While some patients will know when a flare up is coming and can be medicated as needed, others don’t have that foresight, so Spiegel advised health care professionals to always ask whether or not the patient knows.

Non-pharmaceutical therapies have the largest effect in meta-analysis, with peppermint oil being the single most effective, Spiegel said. However, he cautioned that the claim is based on a limited number of studies that were not as rigorous as more recent randomized, controlled trials.

Dietary management, psychological interventions, and exercise all have been shown to reduce IBS symptoms. Since patients frequently report that diet drives their symptoms, dispensing dietary advice — such as eliminating gluten or following a low Fermentable, Oligo-, Di- Mono-saccharides and PolyolS (FODMAP) diet — is easy for physicians to provide, but difficult for patients to follow, Spiegel said.

Adding more fiber is inexpensive and may help some patients, but it also can cause bloating, so Spiegel advised to start low and go slow.

Antispasmotics also remain an option, and Speigel reported seeing some great responses and uses of the drugs for urgency and cramping. Additionally, he prescribes tricyclic antidepressants for some patients and finds them helpful.

Alosetron is still available for women with severe IBS with diarrhea, but with its safety profile — including ischemic colitis and severe obstructing constipation — the drug is not used as much and only after other treatments have failed.

Spiegel said a single course of antibiotics may be appropriate in some patients, but he does not typically use them because he finds other treatments effective.

Even so, he has used lubiprostone for IBS with constipation with some success, as it increases fluid secretion in the intestine. But comparing the number needed to treat, it is the least effective of the IBS agents at 13.

The newest IBS drug, linaclotide, also increases water in the lumen, but it inhibits aberrant nerve firing, which may help reduce pain, Spiegel said. Its number needed to treat is five.

“That’s quite a robust response,” Spiegel said, though he noted that he has not yet prescribed it for patients, because he does not have access to it at the VA. “But based on the data presented, I’m enthusiastic about the large effect size and the data we are seeing.”