What is a breath test?

The hydrogen breath test or breath test is a diagnostic test that is carried out by analyzing breath samples. There are three main types of breath tests: the glucose breath test, the lactose breath test and the lactulose breath test.


What is the purpose of a breath test?

In the gastroenterological field, a breath test allows you to detect changes in the gastrointestinal tract such as bacterial contamination, intestinal malabsorption and deficiency of the intestinal transit, which may occur due to gastrointestinal disorders characterized by flatulence, bloating, diarrhea, abdominal cramping and distention.

Thanks to the glucose breath test, diagnosis of bacterial overgrowth in the small intestine is possible. The lactose breath test is useful in the diagnosis for lactose intolerance and the lactulose breath test is used to measure both the possible presence of bacterial overgrowth and the evaluation of orocecal transmit time (OCTT).


What steps should be taken to help prepare for the examination?

The test is carried out in the morning on an empty stomach, without the patient having smoked or been involved in any physical activity. It is also advised twelve hours before the test to suspend any use of non-essential drugs.


Which patients can undergo a breath test?

The test can be useful for patients reporting gastrointestinal disorders characterized by flatulence, bloating, diarrhea, abdominal cramping and distention.


Is a breath test dangerous or painful?

Undergoing a breath test is simple and non-invasive, and is therefore safe for the patient and the operator.


How is a breath test performed?

The test consists of a collection of breath samples taken before and after breathing into a plastic bag and ingesting a specific sugar dissolved in water, at regular intervals. The exam can last anywhere from two to four hours.