What is IBS-D?

Irritable Bowel Syndrome with Diarrhea (IBS-D), also called Diarrhea-Predominant Irritable Bowel Syndrome (Diarrhea-Predominant IBS), is a chronic gastrointestinal disorder characterized by recurrent episodes of abdominal pain, discomfort and diarrhea. People experience frequent bowel movements, loose and watery stool and abdominal pain. All of these are often accompanied by a sense of urgency and a feeling of incomplete evacuation.

The primary distinguishing feature of this type of IBS is the predominance of diarrhea as the main bowel symptom. In contrast, other versions of IBS may be characterized by constipation (IBS-C) or a combination of constipation and diarrhea (IBS-M).

Although the exact causes of IBS remain unclear, factors like stress, certain foods and gut bacteria may worsen symptoms of IBS-D. Working closely with health care providers can help diagnose and manage the condition effectively.

If you're dealing with IBS-D, know that you're not alone. Many people face similar challenges, and there are ways to help improve your quality of life through proper treatment and support.

In this article:

Understanding Irritable Bowel Syndrome with Diarrhea (IBS-D)

Shedding more light on IBS-D can make it easier to comprehend and less intimidating to manage. Individuals can take proactive steps to improve their quality of life once they have a deeper understanding of the digestive system.

Symptoms

If you're struggling with persistent digestive issues, it's important to be aware of potential signs of a serious underlying problem. "Alarm features" that should trigger an evaluation for something other than IBS include:

• The age of onset after age 50
• Rectal bleeding or black-colored stools
• Diarrhea at night
• Unexplained weight loss
• Severe abdominal pain
• Certain abnormal lab results
• Family history of inflammatory bowel disease (including Crohn's disease or ulcerative colitis) or colon cancer

Primary symptoms of IBS-D include:

• Frequent, loose or watery bowel movements
• Abdominal pain and cramping
• Sense of urgency or inability to control your bowels
• Bloating
• Gas
• Nausea

Causes

The exact cause of IBS-D is unknown. However, understanding the triggers can help manage symptoms. Certain foods or beverages may exacerbate digestive issues of the large intestine and exacerbate symptoms of IBS-D. Specific trigger foods vary from person to person, so those with IBS-D need to identify and avoid their personal problem foods. Common irritating foods and beverages include:

• Dairy products: Milk, cheese, ice cream, etc. Many people with IBS are lactose intolerant.
• Fried and fatty foods: Greasy or high-fat items can be difficult to digest.
• Spicy foods: Chili peppers and other spicy ingredients can irritate the digestive tract.
• Caffeine: Found in coffee, tea, soda and chocolate, caffeine can stimulate the bowels.
• Alcohol: Can irritate the intestines and worsen diarrhea.
• Carbonated beverages: The gas in sodas and sparkling waters can cause bloating and discomfort.
• Certain fruits: Apples, pears, peaches, buckwheat and prunes are high in sorbitol, which can cause diarrhea.
• Beans, broccoli, and other gas-producing vegetables: Can worsen bloating and gas.
• Artificial sweeteners: Certain artificial sweeteners, such as sorbitol and xylitol, are known to cause diarrhea. Other artificial sweeteners may negatively impact gut health.

Lifestyle factors, such as a sedentary lifestyle or poor sleep habits, also have a strong connection to IBS-D. Recognizing and addressing the potential triggers of IBS and treatment options can empower individuals to take a proactive approach to managing their gut issues and improving their overall well-being.

Diagnosing IBS-D

Diagnosing and differentiating IBS-D from other conditions can be a complex process, as the symptoms can overlap with a variety of digestive disorders. Work closely with your health care provider to ensure an accurate diagnosis and appropriate treatment plan.

"Most patients with IBS-D will require a comprehensive workup to rule out other causes of intestinal issues,” says board-certified Internal Medicine Physician Dr. Brennan Kruszewski. “If you're experiencing symptoms, it's important to reach out to your doctor to get a full evaluation."

Risk factors include:

• Anxiety and depression
• Age of under 50
• Being born female
• Family history of IBS

Medical History and Physical Exam

Your health care provider will conduct a comprehensive medical history exam. This involves asking detailed questions about your current health, past medical conditions and lifestyle. They will also ask about family health since having a family member with IBS can increase the chances of you having the condition. The doctor will inquire about your medical background, including any previous diagnoses, hospitalizations, weight loss, surgeries or chronic illnesses. They will also ask about your current IBS symptoms, when they started and how they have progressed over time. Additionally, the doctor will gather information about your personal and family health history, including any genetic conditions, to assess your risk factors.

This health information will inform the diagnostic process and guide the development of an exact course of treatment.

Diagnostic Criteria

The main criterion for diagnosis is the presence of recurrent abdominal pain associated with a change in bowel habits, specifically loose or watery stools. IBS patients must report abdominal pain or discomfort at least 1 day per week in the last 3 months, associated with two or more of the following: pain related to defecation or a change in the frequency or appearance of stool.

Additionally, there must be no evidence of an organic cause for the symptoms of IBS, such as inflammatory bowel disease, celiac disease or malabsorption. A diagnosis of IBS-D is made when the predominant bowel habit is loose or watery stools, as opposed to the constipation-predominant or mixed subtypes of IBS. Once confirmed, a goal of treatment can be made.

Additional Testing

Diagnostic testing and routine allergy testing may be performed to rule out other conditions, but there is no single diagnostic test for IBS-D.

Additional tests may include:

• Blood tests: Blood tests are often used to rule out other conditions with similar symptoms to IBS, such as celiac disease or inflammatory bowel disease. Blood tests can check for signs of inflammation or infection.
• Stool tests: Stool samples may be analyzed to check for signs of infection, malabsorption, or other digestive issues.

There are also a variety of imaging tests that may be used to rule out more serious conditions. These tests include:

• Colonoscopy: This procedure uses a small camera on the end of a flexible tube to examine the colon and look for any abnormalities, including colon cancer and ischemic colitis.
• Flexible Sigmoidoscopy: Similar to a colonoscopy, a flexible sigmoidoscopy explores only the lower colon.
• CT scan or MRI: These imaging tests can provide detailed pictures of the digestive tract to help identify any structural issues.
• Hydrogen breath test: This test measures hydrogen levels in the breath to check for small intestinal bacterial overgrowth, which can contribute to IBS.

Managing and Treating IBS-D

Finding effective ways to manage the condition and reduce abdominal pain can feel like an ongoing challenge. However, there are persistent changes you and others can make to find relief and regain control over your digestive health, such as habit changes and medicines.

Dietary Adjustments

Dietary changes are usually the first line of defense and can play an important role in managing IBS-D. There are different ways to adjust diet. One of the most effective dietary approaches is the low FODMAP diet. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols, which are types of carbohydrates that can be difficult for some people with IBS to digest.

By following a low FODMAP diet, individuals can identify and eliminate the specific foods and drinks that trigger their symptoms. This involves temporarily cutting out high-FODMAP foods, such as certain fruits, vegetables, grains, and dairy products, and then gradually reintroducing them to determine which ones are well-tolerated.

"Although a low FODMAP diet is something that can help manage IBS-D symptoms, it should be something you try under the supervision of a health care provider, as part of a comprehensive treatment plan,” says Dr. Kruszewski.

Lifestyle Changes

Making certain lifestyle adjustments can help provide relief and improve quality of life. One of the key factors is managing stress levels. Chronic stress can exacerbate IBS, so it's important to find healthy ways to cope, such as practicing relaxation techniques like meditation, deep breathing or yoga.

Incorporating regular exercise into one's routine can also be beneficial, as physical activity can help reduce stress and improve gut function. However, it's important to start slowly and listen to one's body, as strenuous exercise can sometimes worsen symptoms of IBS.

Medications and supplements

Many people with IBS-D find relief through a combination of lifestyle alterations and medication. Some of the most common medication and supplement options include:

• Antispasmodic medications: These help to relax the intestinal muscles and reduce abdominal cramping and pain. Examples include dicyclomine and hyoscyamine.
• Encapsulated oil of peppermint supplements: Peppermint has antispasmodic properties that may help soothe the digestive tract. Peppermint oil is available in capsules.
• Fiber supplements: Adding soluble fiber to the diet through fiber pills like psyllium or methylcellulose can help firm up loose stools and promote more regular bowel movements. While fiber may help some people, too much fiber may lead to bloating in some people.
• Loperamide: This over-the-counter medication helps to slow down intestinal transit time and reduce diarrhea episodes. It should be used cautiously, as long-term use can lead to constipation.
• Tricyclic antidepressants: Some medicines have more than one benefit, and recent research from clinical trials has found that certain antidepressants may help with IBS. Low doses of tricyclic antidepressants (TCAs) may be considered as a second-line option.
• Antibiotics: In some cases, antibiotics such as Rifaximin may be prescribed to help reduce bacterial overgrowth in the small intestine.

This content is for informational purposes only and is not medical advice. Consult your health care provider before taking any vitamins or supplements and prior to beginning or changing any health care practices.