SIBO: Symptoms, Causes, and Treatments

Feeling bloated after a meal and unpredictable bathroom trips can be signs of irritable bowel syndrome or IBS. But for some people, it can be something else. Small intestinal bacterial overgrowth (SIBO) happens when there’s an abnormal increase of bacteria in the small intestine, which can trigger digestive symptoms. 

IBS and SIBO often go hand-in-hand, with a large meta-analysis finding SIBO in about 38% of people with IBS across studies. However, it can also be missed or misdiagnosed because the symptoms of SIBO are similar to IBS. 

Continue reading to learn more about SIBO, including its symptoms, causes, risk factors, treatment options, and where to find the best gastroenterologist in Los Angeles for effective relief of SIBO symptoms. 

What is Small Intestinal Bacterial Overgrowth?

Small intestinal bacterial overgrowth happens when too many bacteria grow in the small intestine, which is a place where bacteria are normally present in much lower numbers. When these microbes build up where they do not belong, they start fermenting the food you eat too early in the digestive process. That fermentation can create several digestive symptoms: 

Symptoms of SIBO 

• Loud stomach rumbling
• Gastrointestinal bloating 
• Abdominal pain 
• Changes in your bowel habits, including diarrhea and constipation
• Frequent or increased gas 

Over time, SIBO can interfere with how your body breaks down and absorbs nutrients, which may lead to vitamin deficiencies, unintended weight loss, or ongoing fatigue. 

Small Intestinal Bacterial Overgrowth Causes and Risk Factors

SIBO often develops when the small intestine is not moving food through the digestive tract the way it should. In a healthy gut, gentle waves of involuntary muscle contractions sweep leftover bacteria and food forward between meals. When that movement slows down, bacteria have more time to multiply. 

There are several risk factors for developing SIBO, including: 

• Conditions like diabetes and scleroderma can affect the nerves and muscles that control digestion, which may leave food sitting longer than it should and create a warm, nutrient-rich space for bacteria to grow. 
• Structural changes, including scar tissue from past abdominal surgery, narrowed areas called strictures, adhesions, or certain types of bypass surgery, can cause pockets where bacteria collect and linger. 
• Acid-suppressing medications that can reduce one of the body’s natural defenses against excess bacteria. 
• IBS, immune system disorders, and diets high in refined sugars and carbohydrates can also shift the normal balance of the gut microbiome. 

How is Small Intestinal Bacterial Overgrowth Diagnosed?

Diagnosing SIBO starts with a close look at your medical history and symptoms. From there, many providers recommend a hydrogen or methane breath test, which is a noninvasive test that includes drinking a solution containing lactulose or glucose, then breathing into small tubes over a few hours while your breath is analyzed for gases produced by bacteria. Elevated levels can suggest bacterial overgrowth in the small intestine. 

In some cases, a provider may prescribe antibiotics based on symptoms and risk factors to see if you improve. The most accurate method of diagnosing SIBO is a culture of fluid taken directly from the small intestine, but this requires an endoscopic procedure and is done less often. 

Treatment Options for Small Intestinal Bacterial Overgrowth

Treating SIBO focuses on lowering the excess bacteria and helping your gut heal so symptoms ease up and don’t return. Common treatments include: 

• Antibiotics that can target bacteria in the small intestine while limiting effects on the rest of the body
• Changes to your diet, including eating low-fermentation foods that reduce the types of carbohydrates that bacteria feed on
• A short-term elemental diet, in which you get nutrients through an easy-to-absorb liquid to give the digestive tract a break

Supportive therapies can further improve results and may include: 

• Prokinetic medications to help the small intestine contract and sweep bacteria forward between meals
• Probiotics in some cases 
• Addressing root causes such as slow gut motility, scar tissue from prior surgery, or medication use

Prevention and Long-Term Management of Small Intestinal Bacterial Overgrowth

Keeping the small intestine moving the way it should can help prevent SIBO from coming back. Since your gut has a natural cleaning wave between meals that sweeps leftover bacteria forward, regular eating patterns can help support that rhythm. Other ways you can help support a healthy gut include: 

• Leaving a few hours between meals instead of constant snacking gives your digestive tract time to reset
• Taking a short walk after eating can also stimulate gentle muscle contractions that move food along
• Managing underlying conditions, such as diabetes or connective tissue disorders, that can slow motility over time
• Cutting back on refined sugars and heavily processed carbohydrates to reduce the fuel that bacteria thrive on
• Staying well hydrated, which helps stool move more easily through the system
• Manage stress since chronic stress can alter gut function and make symptoms flare
• Regular follow-ups with the best gastroenterologist in Los Angeles for monitoring, adjustment of treatment plans, and early action if symptoms begin to return

Where to Find the Best GI Doctor in Los Angeles for Effective SIBO Treatment

Living with SIBO can make you second-guess every meal and even avoid enjoying events and meals you once loved because you never know when the bloating, abdominal pain, or urgent bathroom trips will take over your day. The good news is that SIBO is treatable, and when identified correctly, the root causes of SIBO can easily be addressed. 

At Elite Digestive Health, we help patients move beyond guesswork by combining targeted testing with treatment strategies designed to relieve symptoms, support healing, and reduce the chances of recurrence. With a compassionate team of experts, Dr. Benjamin Basseri proudly serves patients across Santa Monica, Century City, West Hollywood, and all of West LA from our conveniently located Beverly Hills office.

Ready to get fast and lasting relief from SIBO symptoms with treatment from the best GI doctor in Los Angeles?