Always Feeling Bloated? Talk to Your Doctor About SIBO

By Shrina Patel, PA-C

Do you feel bloated all the time?

Is your stomach flat in the morning only to look like a bowling ball at the end of the day?

If so, you could be one of the millions of people in the U.S. who have small intestinal bacterial overgrowth — commonly referred to as SIBO for short.

Because symptoms of SIBO are also associated with many other conditions, diagnosing it can be challenging at first. However, once diagnosed it can often be managed with medication and by treating the underlying causes.

At the Center for Digestive Health at Penn Medicine Princeton Medical Center patients have access to advanced diagnostic and treatment procedures for a range of gastrointestinal conditions, including SIBO.

What is SIBO?

Small intestinal bacterial overgrowth is characterized by an abnormal increase in the number or type of bacteria in the small intestine.

While bacteria naturally live in various parts of the digestive system, the small intestine typically has relatively few bacteria compared to the large intestine (colon).

When bacteria populations proliferate in the small intestine they can interfere with digestion and nutrient absorption and cause uncomfortable symptoms.

What are the causes?

The causes of SIBO are multifaceted and often linked to an underlying condition that disrupts the normal functioning of the digestive system.

Motility disorders are among the most common causes of SIBO. When the movement of food and waste through the digestive system is impaired, it can allow bacteria to thrive in the small intestine. Motility disorders are often associated with conditions like irritable bowel syndrome (IBS) and diabetes.

Other common causes of SIBO include:

• Structural abnormalities. Conditions like diverticulosis, surgical adhesions, or strictures can create pockets where bacteria accumulate.

• Low stomach acid. Insufficient stomach acid, whether due to aging or the use of acid-suppressing medications, can decrease the natural defense against bacterial overgrowth.

• Autoimmune conditions. Autoimmune conditions such as lupus and scleroderma can impair motility and can reduce the body’s ability to keep bacteria in check.

In addition, while the food you eat may not directly cause SIBO, it can exacerbate symptoms.

For instance, many bacteria feed on sugar, so foods with certain types of sugar – particularly fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) — may trigger symptoms.

What are the symptoms?

Common symptoms of SIBO include:

• Bloating.
• Abdominal pain or discomfort.
• Diarrhea or constipation.
• Excessive gas.
• Fatigue.

If you experience these symptoms, talk with your doctor and ask about the possibility of SIBO.

Left untreated, SIBO can negatively impact your quality of life, and in severe cases can lead to nutritional deficiencies, weight loss, leaky gut syndrome and chronic conditions like IBS.

How is SIBO diagnosed?

Diagnosing SIBO typically involves a combination of clinical evaluation and diagnostic testing by a gastroenterologist.

One of the most commonly used tests is the breath test, which measures hydrogen and methane gases produced by bacteria in the small intestine. During the test, patients consume a sugar solution and their breath is analyzed over several hours. Elevated levels of these gases are indicative of SIBO. Breath tests can be administered in the doctor’s office or can be performed at home.

Blood tests may also be recommended to identify nutritional deficiencies.

How is SIBO treated?

Short-course antibiotics are normally the first-line treatment for SIBO. In many cases, people with SIBO start to feel better soon after starting antibiotics. Antibiotics for SIBO are generally not absorbed throughout the body, reducing the risk for side effects.

While antibiotics are effective at treating SIBO, there is a chance it can reoccur after treatment and require another course of medication.

Moreover, it is important to address any underlying causes to help prevent reoccurrence.

Can SIBO be prevented?

You may not be able to prevent SIBO, but certain lifestyle adjustments can play a significant role in reducing symptoms and managing the condition, such as:

• Eating smaller meals. Large meals can overwhelm the digestive system and exacerbate symptoms.

• Chewing thoroughly. Properly chewing food aids digestion and reduces the burden on the small intestine.

• Following a low FODMAP diet. Some patients find relief by following a low-FODMAP diet, which limits fermentable carbohydrates that bacteria feed on. Patients may also benefit from avoiding refined sugars and highly processed foods.

• Exercising regularly. Regular exercise can help keep your bowels running smoothly and ensure that waste and bacteria clear quickly from the small intestine.

• Controlling chronic conditions. Making sure chronic conditions, such as diabetes, are under control, can help reduce the risk for SIBO.

SIBO is a complex condition that requires a comprehensive approach to diagnosis and treatment. While it can significantly impact quality of life, proper treatment and management can alleviate symptoms and prevent recurrence. If you suspect you may have SIBO, consult a gastroenterologist for testing and treatment options tailored to your needs.

To find a gastroenterologist with Penn Medicine Princeton Health, call (888) 742-7496 or visit www.princetonhcs.org. 

Shrina Patel, PA-C, is a board certified physician assistant on staff at the Center for Digestive Health at Penn Medicine Princeton Medical Center.