Irritable Bowel Syndrome (IBS)

Causes of irritable bowel syndrome

The cause of irritable bowel syndrome is unknown, but several factors can contribute to or trigger symptoms including:

• Stress, anxiety or depression  
• Medications such as antibiotics
• Inflammation in the intestines
• Fluctuating hormone changes levels, for example during menstruation
• Eating specific foods containing chocolate, alcohol, caffeine, sorbitol or fructose; carbonated drinks, fried, fatty foods or large meals also can trigger IBS symptoms.

Risk factors for irritable bowel syndrome

There are a variety of factors that make you more likely to develop irritable bowel syndrome including:

• Age — younger people are more likely to develop IBS
• Gender — women are more likely to have irritable bowel symptoms
• Genetics — a family history of IBS puts you are at higher risk
• Mental health issues — if you have history of behavioral or mental health, you might be more likely to develop irritable bowel syndrome

Symptoms of irritable bowel syndrome

The most common symptom of irritable bowel syndrome is abdominal pain. Other symptoms that accompany abdominal pain include:

• Bloating
• Gas
• Constipation
• Diarrhea
• White or clear mucus in the stool

Diagnosis of irritable bowel syndrome

Your primary care doctor can diagnose irritable bowel syndrome in a physical exam. Patients presenting with symptoms of IBS represent a large portion of primary care and gastroenterology visits each year.

A physician will typically evaluate your symptoms using the following guidelines:

• Rome criteria — confirms if you have had symptoms at least one day per week for more than three months and meet other criteria such as a change in the way your stool looks or comes out and if you have symptom relief from a bowel movement.
• Manning criteria — looks at how many symptoms you have along with the reduction of pain relieved with passing stool, the amount of mucus in the stool and having unfinished bowel movements.

In order to effectively treat irritable bowel syndrome, your doctor needs an accurate diagnosis, so they may use medical tests to confirm IBS.

Diagnostic testing could include:

• Blood tests — can confirm tissue damage and inflammation in the intestines.
• Stool tests — identify bacterial infections, intestinal parasites or blood in the stool. 
• Sigmoidoscopy or colonoscopy — allows your doctor to visually see inside the rectum and colon to determine the cause of your symptoms
• Imaging tests — x-ray or computed tomography (CT scan) produce images that help your doctor determine the cause of your symptoms

Treatment for irritable bowel syndrome

The goal of irritable bowel treatment is to improve quality of life and prevent flare-ups so you can live a normal life.

Mild to moderate irritable bowel syndrome can be treated with lifestyle modifications such as:

• Avoiding or eliminate food triggers
• Drinking more water
• Exercising
• Establishing healthy sleep patterns

For patients with more severe irritable bowel syndrome, medications may be effective in relieving your symptoms and treating underlying conditions that may be triggering the IBS. Options might include gut antispasmodic, fiber supplements, laxatives and antidiarrheals.