Frequently Asked Questions
The Hydrogen Breath Test is a test that uses measurement of hydrogen in exhaled breath to diagnose various conditions that cause gastrointestinal symptoms.
In normal condition, only colonic anaerobic bacteria are capable of producing hydrogen when undigested food (particularly sugars and carbohydrates) reaches to colon which is in small amount but conditions which causes indigestion leads to more undigested food to reach colon and thus producing large amount of hydrogen.
In conditions like SIBO (Small Intestinal bacterial Overgrowth) where colonic bacteria move back into small intestine and produces hydrogen from food those has not been completely traversed small intestine to be fully digested and absorbed.
These hydrogen produced by colonic and small intestinal bacteria enters into blood flowing through the wall of intestine and reaches lungs where it is exhaled in the breath where it can be measured.
Patient presented with symptoms like,
- Abdominal Bloating
- Flatulence (Excessive passage of gas)
- Diarrhoea
- Excessive Belching
- Abdominal Discomfort
This is seen in conditions like,
- Lactose Intolerance (Milk indigestion) – where lactose which is sugar in milk are not being digested due to deficiency in enzyme called lactase.
- SIBO (Small Intestinal Bacterial Overgrowth) – where colonic bacteria move back into small intestines
- Rapid food transit – where food moves too quickly through intestine before being digested properly
Glucose HBT –
- 50-100 gms of glucose is given orally with 250 ml of water
- To Diagnose SIBO
Lactose HBT
- Lactose 25 gms is given orally with 250 ml of water
- To Diagnose Lactose Intolerance (Milk Indigestion)
Lactulose HBT –
- 10-20 mL of lactulose is given orally
- To Diagnose Rapid Intestinal Transit
- Patients should not take antibiotics for 4 weeks before the test.
- Patients are advised not to eat any slowly digested foods (such as beans, bran and high-fiber cereals) for 24 h prior to the test and should take low fibre diet.
- They should not take any fiber supplements and laxatives 24 h before the test Patients should fast for 12 h before the procedure.
- Patients should not smoke and sleep 2 h before and during the test.
Patient has to exhale in breath analyzer at start of test and then every 15 to 30 minutes as per type of the test for at least 2 hours. Test can be interpreted after completion of test and results are available immediately on completion of test.
It is a breath Test where patient only have to breathe out in disposable pipe connected to breath analyzer machine.
Patient needs to take Glucose, Lactose or lactulose as per requirement in Breath Test. These are natural sugars which produces same symptom from which patient is suffering. A symptom like Abdominal Bloating, Belching, abdominal Discomfort or Diarrhoea can occur which patient has to note down and inform the doctor which also helps in interpretation of results. Although Dose of these sugars are very less and symptoms are mostly mild and transient.
Hydrogen Breath Test helps in proper diagnosis of conditions which causes Gastrointestinal symptoms like Flatulence (Excessive Gas formation and passage), Abdominal Bloating and Discomfort. Hence, Treatment can be individualized as per diagnosis which helps in alleviating symptoms more promptly.