Hydrogen breath tests are often done on gastrointestinal patients in order to better understand possible malabsorption in the body. Irritable Bowel Syndrome patients are often asked to complete this task to see if other issues are going on. Simply put this test measures the hydrogen levels in the breath to diagnose gastro issues like bacterial overgrowth, digestion of dietary sugars, and diagnosing rapid passage of food through the small intestine. Bacteria specifically in the colon produces hydrogen when exposed to unabsorbed food like sugars and carbohydrates. Small amounts of hydrogen is normal but when a large amount is produced this can be a sign of digest or absorption problems.
To be honest, the test is pretty disgusting. There is no prep work the night before except not eating or drinking after midnight. I took a base line test which consists of blowing into a balloon with three breathes of air. After that I had to drink a horribly sweet sugar every 15 minutes for three hours. As someone who cannot handle sugars like this to begin with, it was pretty miserable. I got stomach cramps, felt nauseous and couldn’t drink water the entire time. Thankfully I had my husband next to me as I was kicking and screaming (mentally, not physically) while trying to distract myself watching TV.
It’s not always a conclusive test and this was the case for me. I started with an elevated baseline and it did not change with the addition of the sugars. Patients that have better results than I did from the test are given antibiotics to treat the bacterial overgrowth.
To read more, check out this wonderful source.