Bowel Incontinence in MS: Why It Happens, What to Do About It

Many people with MS have reduced control over bowel movements, but there are ways to take control back.

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Both changes in diet and a variety of medical interventions can help to control bowel incontinence.Peter Dazeley/Getty Images

Multiple sclerosis (MS) can disrupt many different areas of function in your body — not just movement in your arms and legs, but also your vision and speech, according to the National Multiple Sclerosis Society (NMSS). Another common area of dysfunction is the pelvic floor region, where urinary, bowel, and sexual dysfunction are frequent and disabling disorders in people with MS, according to a review published in April 2022 in the Journal of Clinical Medicine.

Bowel dysfunction in particular is a source of frustration and embarrassment for many people with MS and sometimes for their caregivers as well. It’s very common, affecting around 50 percent of people with the disease, notes an article published in July 2017 in the Journal of Neurology.

One form this dysfunction can take is bowel incontinence, or inability to control bowel movements, per the NMSS. People who experience this symptom often fear they could have an “accident” at an inopportune time, without much warning.

But bowel incontinence isn’t disconnected from other bowel symptoms, such as constipation and urgency, according to an article published in December 2018 in the journal Degenerative Neurological and Neuromuscular Disease. In fact, many people with MS experience all three of these issues on a regular basis.

Here’s an overview of how MS can change your bowel function, leading to incontinence — and steps you can take to regain some control over your bowel habits.

How Bowel Incontinence Happens in MS

Normal bowel function depends on a network of signaling throughout your central nervous system, says Tamara Bockow Kaplan, MD, a neurologist at Brigham and Women’s Hospital in Boston.

“The brain and bowel are in constant communication. Normally, the bowel sends information through the spinal cord, which has to get to the brain and then back to the bowel,” Dr. Kaplan says. Your brain considers not just the information from your bowel, but also convenience and social signals, to determine whether it’s time to have a bowel movement.

If this signaling is disrupted at any point, Kaplan says, your bowel may not get the go-ahead to empty at a convenient and socially appropriate time. This can cause a range of disruptive symptoms, especially if you also have MS-related problems in the area, such as reduced sensation in your rectum or reduced control of your outer anal sphincter, the circular muscle at the end of your anal canal.

Related: 8 Things to Try When MS Affects Your Ability to Taste and Smell

Even though it may seem counterintuitive, one of the most common causes of bowel incontinence is actually constipation.

“Extreme constipation can lead to stool backup” in the colon, Kaplan says — making it much harder to control bowel movements when the inner anal sphincter finally opens and the pelvic floor relaxes to allow the muscles in the rectum to push the stool out.

But some people with MS experience bowel incontinence without constipation, or without knowing they’re constipated — especially if the outer anal sphincter isn’t functioning well.

Bowel problems often go hand-in-hand with bladder problems, and not just because they’re both caused by a disruption in nerve signaling affecting the same region of your body.

“Oftentimes when someone has an overactive bladder, they try to self-treat by limiting their fluid intake,” says Kaplan. “That can, in turn, worsen constipation and, in some cases, lead to incontinence.”

RELATED: 11 Icky but Interesting Facts About Poop

Getting Help for Bowel Incontinence With MS

One huge barrier to people with MS getting effective help for bowel problems is that most doctors don’t ask about these issues, says Kaplan. She’s seen this in a research project that involves going through the records of MS patients.

“Doctors aren’t bringing this up, and a lot of times patients aren’t sure how to bring it up,” she says. Patients are also “potentially not aware that this could be related to their MS, or what their neurologist would do about it” if it were related.

So the first step in getting help for bowel problems is telling your neurologist or primary care doctor what’s been happening. “Getting an accurate picture of symptoms is really important,” says Kaplan. “We often base a lot of our management on what patients self-report.”

Your doctor may ask you to keep a journal of your bowel symptoms, along with what you’re eating and drinking, and other potentially relevant behaviors. Patterns related to what you eat or drink may emerge, and your doctor will also get a picture of your overall diet.

How Diet and Medication Can Contribute to Bowel Problems

“I don’t think people realize that the food we eat and what we drink can really make a difference” in bowel symptoms, says Rachael Stacom, nurse practitioner and senior vice president of population health at Independence Care System in New York City.

Not consuming enough fiber or fluids can contribute to constipation, while consuming spicy foods, dairy products, caffeine, and artificial sweeteners can all lead to problems with bowel urgency.

In more difficult cases, it may help to follow a very restricted diet to see what foods might be problematic, Stacom says. Then, “we’ll have people slowly introduce foods to see if that aggravates your stomach.”

Another potential contributor to both constipation and urgency is what kinds of medication you take. Some may have a stimulant effect or bother your stomach, leading to bowel contractions. Others may slow down your digestion, leading to constipation — and possibly a higher risk of incontinence.

Adjusting medication doses may be difficult, especially if they’re working for their intended purpose. But “sometimes there are some easy things we can do, such as adjusting diet and a bathroom schedule” to respond to the effects of the medication, says Kaplan.

RELATED: Is Your Diet Giving You Diarrhea?

Medical Interventions for Bowel Incontinence in MS

Certain drugs can be helpful to manage constipation and bowel incontinence, often in combination with a bowel training routine. “Sometimes the key is to get your bowels on a regular schedule,” says Kaplan.

One technique involves taking a laxative powder — called polyethylene glycol— at the same time each day. “If someone can establish having a bowel movement routinely after breakfast, then that means for the rest of the day they might be free of the fear that they might have an accident,” Kaplan offers.

There are many other drugs to consider if polyethylene glycol doesn’t do the trick, says Kaplan, including stool softeners and stimulants like bisacodyl and senna. But many of them should be used very judiciously, since they can have side effects and their effectiveness may wane as you develop a tolerance to them.

Another useful option for many people with bowel incontinence, Kaplan says, is glycerin suppositories — which you insert into your rectum to induce a bowel movement, usually within 10 minutes. “They essentially help soften the stool that’s in the rectal area, and they’re not chemically absorbed,” she explains. “You can’t overdose on them.”

If you know you’ll be going someplace — from a long car ride to a social function — where you don’t want to risk a bowel accident, you can use a suppository beforehand. “I’ve had so many patients tell me that this was so liberating to them, because they could time their own bowel movement and do it at their convenience,” says Kaplan.

Pelvic Floor PT and Other Solutions to Bowel Incontinence

Kaplan has seen some patients benefit from pelvic floor physical therapies such as pelvic floor muscle training, which may help strengthen both your pelvic floor muscles and your anal sphincter — potentially addressing both bowel and bladder problems, according to a review protocol published in 2018 in The Cochrane Database of Systematic Reviews.

Some people need only one or two sessions with a therapist and can then do the exercises at home, she says.

RELATED: Pelvic Floor Physical Therapy for MS: Help for Bladder, Bowel, and Sexual Function

According to a review published in 2018 in Degenerative Neurological and Neuromuscular Disease, if lifestyle modifications and establishing a bowel regimen fail to effectively treat bowel symptoms such as constipation and incontinence, other measures such as bowel biofeedback and transanal irrigation (TAI) should be considered.

TAI, or using a device to flush out your rectum with water, has been shown to help relieve symptoms in people with MS, according to a study published in April 2016 in the journal Neurogastroenterology and Motility.

And if you still need protection from bowel accidents, wearing adult briefs can be helpful for many people with MS. Just remember that they’re “not all created equal” in terms of absorption, says Stacom. You could also consider applying a skin barrier cream or ointment to any area that may come into contact with your soiled briefs, says the National Association for Continence — especially if you spend most of the day sitting in a wheelchair or have reduced sensation in the area.

The place to start for any of these treatments is to have a conversation with your doctor. “These are very common issues that many people are struggling with,” says Kaplan. But “if doctors don’t bring these symptoms up, patients have to be courageous enough to say, ‘I’m having a problem.’”