The root cause of IBS and similar conditions is similar to the root cause of migraines, fibromyalgia, Crohn's disease, ulcerative colitis, psoriasis, seizure disorders, asthma, is unknown.

In fact, Many medical conditions like IBS do not have a known "root cause". 

However, conditions can be associated with a proceeding or inciting event, for example; food poisoning, abdominal surgery, traumatic injury, severe infection, covid, hormonal changes, prolonged antibiotic use. 

Many patients will go through dozens of tests including X-rays, CT Scans, MRI's, colonoscopies, upper endoscopies (EGD), blood tests and stool tests which will often come back completely negative.

Small Intestinal Bacterial Overgrowth (SIBO) is recurrent in around 40% of the time in most patients with Motility disorders like chronic constipation, chronic diarrhea, gastroparesis, or anyone with a history of upper GI operations. 

These operations can include history of Fundoplication, gastric bypass, colon surgery, small intestine surgery, gallbladder removal or cholecystectomy and more.

It is common to treat (SIBO) a few times per year.

Abdominal distension, occurs when the belly gets measurably larger. This can occur after a meals or for no reason at all. Sometimes this happens progressively throughout the day. However, in some folks this can be persistent all day. 

Major triggers can include

• FODMAP containing foods 
• Constipation
• Diarrhea

Vagus nerve discoordination 
Abdominophrenic Dyssynergia