What Is IBS? Everything You Need to Know About Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a complex condition that causes discomfort from one or several intestinal symptoms including cramping, abdominal pain, bloating, gas, and diarrhea or constipation, or both. IBS symptoms range from uncomfortable to debilitating. In some cases, diet modification and lifestyle changes can help manage symptoms. Severe cases of IBS may require medication.

What is irritable bowel syndrome?

Irritable bowel syndrome is a group of symptoms labeled a functional gastrointestinal disorder. This means it impacts how the gastrointestinal system functions, rather than causing changes to the tissue in the intestines. IBS is not visible in a physical examination of the intestine.

Most people have gastrointestinal complaints at some point in their lifetime. Many people sporadically have a sensitive stomach. Estimates report that 10 to 20 percent of the population globally is affected by IBS, making it one of the most common functional gastrointestinal disorders. People affected by IBS have complaints such as the urge to have a bowel movement (bowel urgency), diarrhea, distended abdomen, bloating, abdominal pain, and constipation. These symptoms might be so severe that they impair quality of life.

IBS can be diagnosed in adults of all ages. IBS symptoms appear before the age of 35 in about half of people impacted by the disorder. Overall, women are more likely to live with IBS than men.

IBS is a very individual disorder based on a person's specific symptoms. IBS may vary slightly for each person, but common signs and symptoms include:

• Abdominal pain, bloating, or cramping that is either relieved or worsened by a bowel movement
• Frequent flatulence
• Diarrhea
• Constipation
• Mucus in the stool
• Increased pain and discomfort with stress

How does IBS develop?

Researchers have yet to determine one clear cause for irritable bowel syndrome.

The gut-brain axis

One theory is that altered brain-gut interactions (“gut-brain axis”) are responsible for IBS. This means the signals between the brain and the intestines might not be functioning as they should. This could lead to hypersensitivity to digestive processes. The result might be pain, diarrhea, or constipation in a person with IBS, where a person without IBS wouldn’t experience those symptoms.

Stress and IBS

There is believed to be a strong connection between stress and IBS symptoms. Stress hormones may worsen IBS symptoms, making a stressful event an IBS trigger. The pain of IBS can also cause stress, creating a positive feedback loop where IBS and stress feed off of one another. The autonomic nervous system, which controls responses to stress, is believed to be overactive in people with IBS.

Learn more about stress and IBS.

Post-infectious IBS

People with IBS also experience impaired mobility and motility of the intestine. This means food may not be digested and transported through the intestine at normal speed. The disturbed motility may lead to bacterial overgrowth in the intestine.

In many cases, IBS first occurs following a gastrointestinal infection. This is referred to as post-infectious irritable bowel syndrome. It is assumed here that post-infectious IBS is a kind of “scar” in the infected intestine. Irritable bowel symptoms can persist for weeks, months, or even years after severe gastrointestinal infection.

IBS and genetics

It’s believed that IBS may run in families. Environmental factors also assume a role in the development of this condition.

Why is IBS so distressing?

IBS usually impacts a person’s life negatively. Constant worrying about the need to access a restroom, plus the physical discomfort and pain of an IBS attack, can create stress that impacts quality of life. Gastrointestinal symptoms like bowel urgency, abdominal cramps, flatulence, and bowel sounds can complicate one’s social life and work.

How is IBS diagnosed?

IBS is usually diagnosed after many other gastrointestinal diseases and disorders are excluded. A gastrointestinal (GI) specialist will conduct tests to rule out food intolerances and diseases of the gastrointestinal tract. A GI specialist will run tests specific to your symptoms that might include a colonoscopy or stool examinations. A specific IBS test using different blood parameters (biomarkers) is still in the trial phase.

IBS can be diagnosed if other conditions have been ruled out and if a certain set of criteria called the Rome IV criteria are fulfilled. The person must experience recurrent abdominal pain, at least one day per week, for the last three months. At least two of the following signs also need to be present:

• Pain is related to bowel movements
• Change in bowel movement frequency
• Change in the form or appearance of stool

Symptoms must have appeared at least six months before the diagnosis can be made.

How is IBS treated? What are the IBS treatment options?

IBS affects each person differently, and each person responds differently to varying types of treatments. There is no one treatment method that is the standard of care for IBS, but people may find relief from one or a combination of different treatment options. A system and treatment diary or tracker may help a person understand which treatments are most beneficial. The Cara Care app has a symptom and medication tracker you might find useful.

• The low-FODMAP diet is believed to be effective at relieving symptoms in more than 70 percent of those with IBS.
• Food intolerances: Eliminating food intolerances with the guidance of a nutritionist may be useful at managing symptoms.
• Psychotherapy, biofeedback, and stress relief techniques are believed to reduce symptoms.
• Other factors: Moderate activity and emotional peer support (for example in self-help groups) is believed to have a positive effect on symptom reduction.

Which medications help with IBS?

Some IBS medications can relieve various symptoms of irritable bowel syndrome. Medications for IBS work by addressing and alleviating symptoms. Medications for IBS do not combat the root causes of IBS. In addition to probiotics, and antispasmodic or spasmolytic substances (medication to suppress muscle spasms), herbal remedies, and antidepressants are also occasionally used to treat IBS-related pain.

Is IBS dangerous?

Since the quality of life of people with IBS is often impacted, many worry about whether life expectancy is reduced for those who suffer from IBS for a long period. Currently, there is no data to support a reduction in lifespan for people with IBS.