Constipation in Multiple Sclerosis

One of the more uncomfortable and unpleasant symptoms of multiple sclerosis (MS) is constipation. Studies suggest that at least 50% of people living with MS experience constipation and that 25% have recurrent bouts.

While constipation can affect anyone, the underlying causes can be different in people with MS. Not only is constipation more likely to be persistent or recurrent, but it can often be very painful.

This article takes a look at the causes of constipation in people with MS, as well as the ways that this common but frustrating symptom can be treated or prevented.

Common Causes of Constipation in MS
Verywell / Emily Roberts

Symptoms of Constipation With MS

The symptoms of constipation in people with MS are really no different than constipation in anyone else. Where they can differ is in their frequency.

In some people with MS, constipation will gradually worsen as the disease progresses. Others with relapsing-remitting MS (in which MS symptoms come and go) will have recurrent bouts of constipation.

Constipation is diagnosed when there are at least two of the following symptoms in at least 25% of bowel movements:

  • Three or fewer bowel movements per week
  • Straining during a bowel movement
  • Hard or lumpy stools
  • A sensation that you haven't fully emptied the bowel
  • A sensation of a bowel blockage or obstruction
  • The need to physically remove hard stools (with fingers or an enema)
  • Needing laxatives regularly to have bowel movements

Causes of Constipation With MS

There are two factors involved with having normal, healthy bowel movements. Firstly, the stool must continuously move through the intestines. Secondly, there must be enough water in the stool to ease the passage of the stool. If one or both of these factors is impaired, constipation can occur.

MS can cause constipation by directly impairing intestinal motility (movement). Lifestyle factors can contribute by reducing the amount of water needed to keep stools soft. Certain medications can also impair normal bowel function, leading to constipation.

Neurological Factors

Multiple sclerosis (MS) is a disease in which the immune system attacks and destroys the protective covering of nerve cells in the brain and spinal cord. This affects nerve signaling and the way that parts of the body function, including the digestive tract.

In people with MS, this can lead to neurogenic bowel dysfunction in which the intestines do not contract as they should to keep stools moving. As a result, stools will travel slowly through the intestines and impact as they hit certain junctions, growing larger and harder to pass.

Lifestyle Factors

An important component of normal bowel function is physical activity, such as walking or exercising. Because MS can cause progressive weakness, fatigue, and spasticity (spastic movements), people will often become less active as the disease gets worse,

On top of this, it is common for people with MS to cut back on drinking water due to neurogenic bladder dysfunction (the nerve-related loss of bladder control). This can lead to chronic dehydration which only worsens constipation.

Which MS Medications Cause Constipation?

Constipation is a side effect of many of the drugs that people with MS take to control their symptoms, including:

  • Antidepressants: Tricyclic antidepressants such as Elavil (amitriptyline), Norpramin (desipramine), Sinequan (doxepin), and Tofranil (imipramine) are known to cause constipation.
  • Painkillers: These include medications containing morphine or codeine as well as prescription pain-relievers like Ultram (tramadol).
  • Anticholinergics: These include medications like Detrol (tolterodine) used to treat MS-related bladder dysfunction.

How to Treat Constipation With MS

The treatment of constipation in people with MS is largely the same as anyone else. It involves the combination of exercise, diet, and medications if needed.

Over-the-counter medications used to treat constipation include:

  • Fiber supplements: Also known as bulk-forming laxatives, these include products like Metamucil (psyllium) and Citrucel (methylcellulose).
  • Stool softeners: These include products like Colace (docusate) that add water and oil to stools.
  • Lubricants: These are products like mineral oil that are taken by mouth to make stools slippery.
  • Osmotic laxatives: These include laxatives like Miralax (polyethylene glycol) and Phillips Milk of Magnesia (magnesium chloride) that keep water in the intestines.
  • Stimulant laxatives: These are laxatives like Dulcolax (bisacodyl) ad Senokot (senna) that speed the contraction of the intestines.

Prescription medications used to treat constipation include:

In people with advanced MS, bowel movements may be so restricted that stools may need to be physically removed with an enema or digital disimpaction (in which a gloved finger manually removes stool).

Prevention

Constipation is common in people with MS, but the good news is that there are things you can do to prevent it or at very least reduce its frequency.

Among some of the more useful tips:

  • Drink eight 8-ounce glasses of water per day.
  • Eat plenty of dietary fiber, including whole grains and a variety of fruits and vegetables.
  • Stay active, exercising regularly within your physical limitation. This may involve walking, swimming, biking, or yoga.
  • Establish a time each day to use the bathroom (referred to as bowel training). This can help your body become accustomed to a predictable toilet schedule.

Are There Tests to Diagnose the Cause of Constipation With MS?

Constipation can often be diagnosed with a review of your symptoms, diet, and medical history. But, when MS is involved, it can get even more complicated given the possible causes.

If you have MS, your healthcare provider may want to do a complete physical exam. They may also order tests to evaluate your bowel function, such as:

  • Anorectal manometry: This involves the insertion of a narrow tube into the rectum which is then inflated and pulled back through the anal sphincter muscles. This measures the coordination of the muscles in your bowels.
  • Balloon expulsion test: Often used alongside anorectal manometry, this test measures the amount of time it takes to push a water-filled balloon out of your rectum.
  • Colonic transit study: The test tracks the progression of a swallowed capsule (filled wither with either a radioactive tracer or a tiny camera) as it moves through your digestive tract. This can identify intestinal blockage or problems with intestinal motility.

When to See a Healthcare Provider

One of the biggest concerns about constipation in people with advanced MS is the risk of a bowel obstruction. The loss of intestinal motility can become so profound the mass of hardened stool can cause tears and bleeding as it passes through the intestine, causing bowel perforation.

Do not hesitate to rush to your nearest emergency room if you experience signs of bowel perforation, including:

  • Sudden and severe pain spreading across the abdomen
  • Severe abdominal cramps
  • Noticeable abdominal swelling or bloating
  • Nausea and vomiting
  • Rectal bleeding
  • Fever with chills
  • Extreme weakness

Summary

Constipation can affect anyone, but, in people with MS, it can often be chronic and worsen over time. It is largely due to the loss of bowel function as MS progressively damages nerves throughout the body. Lifestyle factors, such as dehydration and physical inactivity, can also contribute.

Diagnosing constipation in people with MS may involve a battery of tests to identify problems with intestinal motility. The treatment may involve over-the-counter or prescription drugs as well as changes in diet and exercise. An enema can also help if needed.

A Word From Verywell

Chronic constipation should never be considered "normal." Irrespective of whether you are older or younger, see your healthcare provider if the symptoms are chronic, severe, or worsening.

In the end, all you may need are a few lifestyle adjustmens to make things the. But, at other times, constipation may be a sign of something imminently more serious, such as colon cancer.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. National MS Society. What causes MS?

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By Julie Stachowiak, PhD
Julie Stachowiak, PhD, is the author of the Multiple Sclerosis Manifesto, the winner of the 2009 ForeWord Book of the Year Award, Health Category.