Thank you for sharing this information. I have been diagnosed with IBS-D. Recently had a positive breath test for SIBO. Started Xifaxan a few days ago but I don't notice any difference in my symptoms. Some of the symptoms actually seem more pronounced. I had the SIBO breath test in the doctor's office. The breath testing machine made an alarm noise at the 3rd and forth 20 minute check. Both time the medical assistant said she had to calibrate the machine. 'I"m wondering if the test was even accurate. I also do not have any upper GI symptoms (heart-burn, belching, indigestion , nausea) which I thought was common with SIBO. I'm questioning if I even need this antibiotic but the doctor feels I do. Any thoughts on this?