What doctors wish patients knew about irritable bowel syndrome

Digestive discomfort has become an all-too-common complaint. And one condition that stands out for its bewildering array of symptoms and challenges is irritable bowel syndrome (IBS). It is a chronic gastrointestinal disorder that can disrupt daily routines, dampen quality of life for patients with IBS feeling frustrated and isolated.

But as understanding of the condition continues to evolve, so does the approach to managing and living with irritable bowel syndrome. Knowing what to keep in mind will help patients navigate life’s digestive maze despite the complexities of IBS.

While IBS affects about 10% to 15% of adults in the U.S., only 5% to 7% of adults have been diagnosed with the disease. Irritable bowel syndrome is also more common in women with almost twice as many women having it than men, according to the American College of Gastroenterology.

The AMA’s What Doctors Wish Patients Knew™ series provides physicians with a platform to share what they want patients to understand about today’s health care headlines.

In this installment, Suma Magge, MD, a gastroenterologist at Norwalk Hospital in Connecticut, discusses what patients need to know about managing—and living with—irritable bowel syndrome.   

“It is a chronic disabling disorder that’s considered to be functional in nature and is usually characterized by abdominal pain and changes in bowel habits,” Dr. Magge said. “That’s the basic definition.”

“IBS can then be further subtyped into diarrhea predominant irritable bowel versus constipation predominant irritable bowel or even a mixed picture,” she said. “In addition to that, a lot of patients will have more pain or even abdominal bloating.”

“So, it’s a whole bunch of symptoms that patients can have, but it’s trying to decipher whether these patients have irritable bowel syndrome or some disease process going on,” Dr. Magge said.

When it comes to diagnosing IBS, “it honestly depends on the age of the patient and looking for any red flags they may have in terms of their symptoms,” Dr. Magge said. “Red flags, from my perspective, are patients who are older than age 50, have unexplained weight loss, a family history of a gastrointestinal malignancy, blood in their stool, or any abnormal laboratory values—like they’re anemic.

“If they have any of these red flags, I work them up further before coming to a diagnosis of irritable bowel syndrome,” she added, noting that IBS “is a diagnosis of exclusion.”

For example, “anybody age 50 or older I tend to work up to make sure there’s nothing else going on,” Dr. Magge explained. “But for younger individuals, I may do a few basic tests to rule out celiac disease or inflammatory bowel disease like Crohn’s or ulcerative colitis, which can mimic or have similar symptoms to irritable bowel syndrome.”

Additionally, “any symptoms overnight—what we call nocturnal symptoms—are red flags,” she said. “So, if a patient is waking up at night with a lot of diarrhea that’s suggestive of maybe there is something else going on.”

“Diet is a huge component in patients with irritable bowel syndrome. It’s probably No. 1-through-5 in terms of treatment for these patients,” said Dr. Magge. “And it seems like the food that we eat causes some sort of hypersensitivity in these patients—altered motility and even increased fermentation in the colon.

“As a result, if patients eat the wrong thing, they can have a lot of the symptoms that we talked about,” she added.

The first-line diet that Dr. Magge and other gastroenterologists often recommend “is the low FODMAP diet—and that stands for fermentable, oligosaccharides, disaccharides, monosaccharides and polyols,” Dr. Magge said.

“When we ingest carbohydrates, the bacteria in our small intestine ferment them, create a lot of gas and basically bring in a lot of fluid into the intestine causing patients to have a lot of diarrhea,” she said. “The hypothesis is for patients to be on a low FODMAP diet, so they're not digesting a lot of these specific carbohydrates and as a result they're having less gas, less bloating, and less diarrhea.

“That's the diet we actually recommend once we've done any preliminary testing,” Dr. Magge added. “The one thing though is the low FODMAP diet is a very restrictive diet. It’s an elimination diet, so we recommend—unless they’re very savvy—to see a nutritionist to help with it.”

“So, the goal is to go through a patient’s diet, eliminate the high FODMAPs and consume more of the low FODMAPs, but then reintroduce things as you get better to see if you can tolerate them,” she said.

“Usually, patients who actually have an autoimmune disease—like celiac disease—where they’re not able to digest gluten, they are always 100% on a gluten-free diet,” said Dr. Magge. But “there is a subset of patients with irritable bowel syndrome who also have gluten sensitivity.

“So, they don’t have true celiac disease, but when they digest gluten, they do have similar symptoms to IBS,” she added. This includes “diarrhea, bloating, pain, increased flatulence and sometimes constipation. But more frequently it’s diarrhea.”

“As a result, one of the things that we do suggest to our patients with IBS is to try a gluten-free diet,” Dr. Magge said. “Another diet is lactose-free—so eliminating dairy—because a lot of patients have lactose intolerance, and a lot of those symptoms actually mimic irritable bowel syndrome as well.”

“Because the symptoms of IBS are so widespread, there’s not one main medicine to treat patients. It’s really based on what their symptoms are,” Dr. Magge said. “If it’s diarrhea, then focusing on anti-diarrheals and there are actually some new prescriptions available for diarrhea predominant irritable bowel syndrome that prevent this surge of fluid to come into the small intestine so that they don’t have that diarrhea and the bloating.”

“The same goes for patients who have constipation predominant IBS. There are medications to help them become more regular,” she said. “There are also medicines for cramping, abdominal pain, , and bloating.”

“A lot of it is symptom management. So, when I see a patient with IBS, I really try to get a sense of what their symptoms are and then I’ll target my treatments at their symptoms,” Dr. Magge said. “There are prescriptions, but there are also even over-the-counter medicines like prebiotics, probiotics, which are also really popular.”

“There are also medicines like IBgard, which is an over-the-counter medicine that contains peppermint oil,” she said, noting it is “an herbal preparation, which has been shown to help with spasm.”

“IBS is so common. I see a lot of young patients who have it during high school and then college years and then it goes away,” Dr. Magge said, noting “it honestly varies from patient to patient.”

“Some patients suffer from their symptoms chronically for years and years. Other patients have it for a short period of time and then it goes away,” she said. “There’s also a subset of patients where they’ve had some sort of gastrointestinal bug—they ate at a restaurant and then had a gastrointestinal bug the next day.”

“As a result, it can cause a post-infectious irritable bowel syndrome. So, that patient may have been completely fine and then after eating, they have a gastrointestinal bug and then for the next five months they’re having diarrhea on a regular basis,” Dr. Magge explained. “We’re actually seeing that in a lot of patients who have had COVID-19.”

“Long COVID can cause gastrointestinal symptoms and we’ve seen a whole slew of symptoms including diarrhea, constipation, slow motility, feeling full nausea,” she said, noting that these gastrointestinal symptoms “can resolve. I’ll treat them based on their symptoms and then within a few months they do improve.”

“There are a lot of factors that influence irritable bowel syndrome and one of them is stress,” Dr. Magge said, noting “that’s probably one of the major risk factors that contributes to IBS, and it just becomes a vicious cycle.”

“When I see patients, I really assess what the degree of stress in their life is because no matter what I do, if their stress is just out of control, the cycle’s not going to stop. Their symptoms are going to continue,” she said.

There are also times “we look at alternative treatment options for irritable bowel syndrome,” Dr. Magge said. For example, “there’s cognitive behavioral therapy.”

Also, “some of the treatment for irritable bowel syndrome is medicines that are used in mental health—antidepressants,” she said. “We sometimes use low-dose antidepressants, which can help with the pain component of IBS, but also helps with the anxiety, depression and stress part of IBS and really can calm things down.”

As with many aspects of life, exercise does play a role too, Dr. Magge said, noting that “somebody who exercises, keeps an active and healthy lifestyle, totally helps with keeping IBS in check and making sure your symptoms are not so flared.”

Sleep also plays a role in managing—and living with—IBS.

“If you don’t have enough sleep, the effects of that could accentuate the symptoms of irritable bowel syndrome,” she said. That’s because “then, as a result, you’re stressed out, you’re tired. It’s this vicious cycle.”

When it comes to taking probiotics, “the data shows that it can help in patients who have more bloating type symptoms,” Dr. Magge said. “But we don’t recommend it on a regular basis unless they have bloating.

“Then I might suggest they try to take it for six weeks or so to see if there’s any benefit,” she added. And if there is a benefit from taking the probiotics, “they can continue taking it long term.”

“Probiotics, in general, don’t really have many side effects because it’s essentially giving good bacteria back to the gut,” Dr. Magge said, noting it can help improve gut health because it is “well tolerated. It’s almost like a vitamin. So, if they benefit from it, I will recommend taking it.”

“Irritable bowel syndrome is a functional disorder. So, if you take a look into a patient’s colon with IBS and you were to take biopsies, there’s no inflammation there,” Dr. Magge said. “Patients will be symptomatic, and it’ll be uncomfortable for them, but if they don’t take any medicines at all or not treat it at all—that’s OK. There’s not going to be any long-term consequences of it.”

That stands in contrast with a patient “who has ulcerative colitis or Crohn's disease, they can have small bowel obstructions, they'll become anemic and there are really severe consequences,” she added. “With irritable bowel syndrome, it's more so that they'll just be uncomfortable, and some patients won’t do anything about it whereas other patients are just so cognizant of their symptoms that they really want to be on these treatments.”

“After three to four months, if you’re having symptoms and it’s not going away, visit your doctor,” Dr. Magge said. “If it persists, that’s the time to seek out your primary care doctor or get a referral to a gastroenterologist to do some further testing.”

“IBS is really cumbersome to patients. It affects their daily life because it affects you trying to go to work and do normal function with abdominal pain, bloating, diarrhea, constipation,” she said. “And trying to worry about your toileting habit is really hard.”

“There’s a lot of research that’s being done to see if we can get better treatments for it, but it’s just something that affects a lot of people and we’re seeing it on a regular basis,” Dr. Magge said. “Most of my consultations are for irritable bowel syndrome and a lot of it is driven by stress.”