Is Your Chronic Diarrhea a Symptom of IBS?

Diarrhea refers to bowel movements (stool) that are loose and watery.  If you have loose stools three or more times in one day, you have diarrhea.*


Acute diarrhea lasts a short time - usually two to three days. Many people experience acute diarrhea once or twice a year, and it can be treated with over-the-counter medications.

Chronic diarrhea - diarrhea that lasts for four weeks or more - can indicate a serious chronic disorder, such as inflammatory bowel disease (IBD) or irritable bowel syndrome (IBS). (Read about the difference between the two here.)


Chronic diarrhea symptoms may be continual, or they may come and go. Regardless, we recognize that they can have an enormous impact on your mental, emotional and social health. 

Know that there are options available to you. The sooner you can identify the cause and receive a confident diagnosis, the sooner you can begin the right treatment for you

What Causes Chronic Diarrhea?

Damage to the intestine's epithelium (outer, protective layer) caused by a bacterial or viral infection is a very common cause of diarrhea. When the epithelium is damaged, absorption of water in the gut happens very inefficiently, resulting in the loose, watery stools associated with diarrhea. 

The development of acute diarrhea into chronic diarrhea is less well understood. As noted above, chronic diarrhea can be a symptom of chronic illnesses like IBS and IBD

We do now understand one pathophysiologic sequence that identifies gastroenteritis (food poisoning) as a major root cause of diarrhea-predominant IBS (IBS-D). In fact, research has shown that 1 in 9 people who experience food poisoning go on to develop IBS with diarrhea.

In these cases, IBS can develop quickly, or it can develop many years after the initial infection. Patients often don't remember the original instance of food poisoning that may have led to IBS.

Epithelial Tissue

Can One Instance of Food Poisoning Lead to Chronic Diarrhea?

Yes, it can. In fact, people who've had food poisoning in the past have a 1 in 9 chance of developing IBS in the future.

It has to do with a toxin called Cytolethal Distending Toxin B, or CdtB for short. It turns out that every one of the most common bacteria that cause food poisoning releases CdtB

When a toxin like CdtB enters your body, your immune system fights back with an antibody - in this case, anti-CdtB.


Anti-CdtB can confuse your body into developing another antibody called anti-vinculin. This harms a naturally occurring protein in your body called vinculin that helps cells migrate and connect to each other. 

This is an autoimmune response and leads to gut nerve damage and improper functioning of the Interstitial Cells of Cajal (ICC) and Migrating Motor Complexes (MMC), which regulate the contractions of your gut

This can ultimately result in diarrhea-predominant and mixed-type (diarrhea with constipation) irritable bowel syndrome, sometimes many years after the initial infection.

Find Out If Your Diarrhea Is

IBS With ibs-smart™

ibs-smart™ is a blood test that can quickly and accurately diagnose IBS with a diarrheal component (IBS-D and IBS-M). It’s the only licensed, patented test that can measure validated biomarkers in your blood that indicate IBS with 96% - 100% certainty.

By accurately diagnosing your IBS and identifying the cause (a microbiome disruption caused by an infection), ibs-smart™ can expedite your path to treatment and prevent years of potentially unnecessary procedures like colonoscopies.

You can order the test through an telehealth prescriber or request a testing kit to take to your next doctor’s appointment.

IBS After Food Poisoning

A significant volume of research shows a clear link between food poisoning and irritable bowel syndrome (IBS).

Chronic Diarrhea & IBS

Chronic diarrhea can indicate disorders, such as inflammatory bowel disease (IBD) or irritable bowel syndrome (IBS).


While irritable bowel syndrome and inflammatory bowel disease share some symptoms, they are completely different illnesses. 

ibs-smart™️ is the only licensed, patented antibody blood test for the diagnosis of IBS. See the full list of patents here

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ibs-smart™️ is brought to patients by Gemelli Biotech. 

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