Leo Treyzon, MD -  - Gastroenterologist

Leo Treyzon, MD

Gastroenterologist & Clinical Nutrition Specialist located in Cedars Sinai Medical Towers & West Los Angeles, Los Angeles, CA

Small Intestinal Bacterial Overgrowth (SIBO) Specialist

Dr. Treyzon is skilled in advanced techniques used in the diagnosis and management of small intestinal bacterial overgrowth, or SIBO, providing patients in and around the Cedars Sinai Medical Towers, Los Angeles, CA, area with customized plans of care based on their specific needs for optimal results and long-term relief of symptoms.

Small Intestinal Bacterial Overgrowth (SIBO) Q&A

What is SIBO?

There is normally a high concentration of bacteria in the colon, or large intestine, with a much smaller concentration in the small intestine. Peristaltic contractions (rhythmic contractions that propel food throughout the digestive tract) occur at regular intervals in a fasting state, about once every 90 minutes, and are partly responsible for keeping the bacteria down in the colon where they belong. However, in some people these rhythmic contractions do not occur as regularly as they should, allowing bacteria to migrate backwards from the large intestine up to the small intestine in abnormally high concentrations. This large amount of small intestinal bacteria can digest some foods before they can be absorbed by the small intestine, causing a variety of symptoms.

What are the Symptoms of SIBO?

SIBO can cause one or multiple of the following symptoms. Bloating and gas are very common SIBO symptoms.

  • Bloating
  • Gas
  • Abdominal pain and/or cramping
  • Diarrhea
  • Constipation
  • Fatigue
  • Nausea

How is SIBO Diagnosed?

The diagnosis of SIBO is typically made by a breath test called a “lactulose hydrogen breath test”, which is often available as a take-home kit. Above are video instructions explaining this test in detail. During this test, the patient will deliver a total of 10 breaths into 10 separate test tubes via an inflatable bag over the course of 3 hours. After the first sample baseline breath is collected, the patient will ingest a non-absorbed sugar called lactulose on an empty stomach. There are then 9 more sample breaths to be collected every 20 minutes at this point in the test. This sugar is not absorbed, but it does reach the bacteria in the small intestine, which metabolize it and produce one or more gases such as hydrogen and methane. These gases are excreted in the breath and can later be measured in a lab. The quantities of these gases and the amount they change over the course of the test is indicative of the amount of bacteria in the small intestine (large amounts of gas indicates a “positive” breath test). A “positive” breath test indicates the patient has SIBO.

How is SIBO Treated?

The first line of SIBO treatment is often antibiotics. The type of antibiotic depends on the type(s) of bacteria that were over-produced during the breath test, the patient’s symptoms, and his/her clinical history. SIBO is a problem that can recur in some people, and so multiple rounds of antibiotics are sometimes necessary. Dietary modification, specifically, the low FODMAP, low fermentation, and SIBO diets are extremely helpful for some people in mitigating symptoms of SIBO. For people with recurrent SIBO, pro-motility medicine is another option.

Insurance Accepted

Here is a list of just some of the plans we accept, please contact our office if you have any questions.

Anthem Blue Cross of California
Director's Guild (DGA)
Motion Picture Industry Health Plan
United Healthcare
Writers Guild

Words from our patients

  • "I couldn't wait to log onto Yelp to give him a much deserving review. He is fantastic!"

    Helen S. - Yelp
  • "I'm amazed at how caring and helpful Dr. Treyzon is. It all started with an email inquiry to his receptionist Amie (who is also very kind and quickly replies to email)."

    Neirreth J. - Yelp
  • "Dr. Treyzon is one of the absolute best doctors I've ever been to. He's got a great bedside manner, he is intelligent, honest, listens and is an all around great guy."

    Beth Q. - Yelp
  • "Dr. Treyzon is one of the only doctors I've ever met that truly listens to his patients and doesn't give up on figuring out what's wrong."

    H.H. - Yelp
  • "Dr. Treyzon is one of the most responsive and thorough doctors I have dealt with. I've seen 5 different gastroenterologists across CA and MA, Dr. Treyzon is the best..."

    Matt M. - Yelp
  • "Dr. Leo Treyzon is an extremely intelligent, likeable and dilligent doctor. He is always on the cutting edge of the latest treatments and technologies."

    Sean S. - Yelp
  • "Great doctor. Great crew. Cannot recommend more highly!"

    J. Marvin C. - Yelp
  • "He is kind, doesn't rush me, listens to my concerns, and is systematic in his diagnoses."

    Mrs. S. - Yelp
  • Dr. Treyzon actually spent an incredible amount of time researching my rather arcane issue and then came up with a creative and innovative solution."

    Baruch T. - Yelp
  • "My OB-GYN referred me to Dr. Treyzon, and I have to say, he was absolutely wonderful."

    Julie S. - Yelp
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