Healthy intestines normally have many types of bacteria. In SIBO, the bacteria living in your small intestine are out of balance and are causing GI symptoms. This imbalance may be due to loss of helpful bacteria or abundance of certain types of bacteria.
Many chemicals, enzymes and immune factors are involved in keeping the bacteria in your small intestine in balance. The normal movement of the intestine and timely emptying of food are also important. Any conditions that affect these processes may cause SIBO.
Bacteria in the small intestine breaks down food into gas and nutrients. Extra bacteria may lead to extra gas. The extra bacteria may also consume certain vitamins and substances important for your digestion. This can affect your nutrition in the long term.
The common symptoms can include:
SIBO is diagnosed when a patient has GI symptoms and evidence of extra bacteria in the small intestine. Some medical experts have agreed on levels of normal and abnormal bacteria.
The most common way to indirectly measure the amount of bacteria in your small intestine is with a hydrogen breath test.
Your provider will advise you to avoid certain medications like antibiotics and laxatives for a few weeks prior to your test. They will also give you instructions on a diet to follow the day before your test.
During this test you will ingest a sugar. This sugar will be broken down by bacteria in your small intestine. The gas byproducts will be given off your body through your breath. The hydrogen level in your breath will be analyzed during a 3-hour period. A hydrogen level above the cut-off suggests excess bacteria.
SIBO can be treated with a short course of antibiotics to help bring the level of bacteria to a healthy balance. However, SIBO can reoccur after treatment and may require repeat treatment.
Your providers may also try to address the underlying factors leading to your SIBO.
Ami J. Panara Shukla, MD, University of Miami, Miami, FL – Published April 2024.