I had SIBO for quite some time before changing doctors 3 times to find one who knew how to test for SIBO. I can tell you that I took Xifaxan and like all PPI's once I was off, the symptoms return. They return because most doctors have it wrong - we need acid to digest, not block it. PPI's and other antibiotics treat the symptom. Symptoms return once you go off the PPI or antibiotic. Read through this thread and you will find some suggestions - I started with a prebiotic and a probiotic, eventually going off the prebiotic after testing and then eventually off the probiotic after testing, took Dr. Shade's Bitters #9 ten minutes prior to eating and taking slow deep breaths to get the digestive juices flowing, Low Fodmap can be helpful but you also need to find foods on that list that you can tolerate as it can be a very restrictive diet (example: I love avocados and continued to eat them without any effects), I also went gluten free as gluten is a digestive tract disruptor and upsets the microbiome (you'd be surprised how many gluten free products there are now and they actually taste good - Udi's bread, gluten free pastas, etc., - dairy free and eventually slowly adding in one product at a time to see if I could tolerate it, drink Kefir and eat other fermented foods such as pickles (but only from the refrigerated section to keep it from spoiling, and sugar free (using organic Stevia instead in coffee and tea). It's a process and takes time and consistency to get to feeling better and rid yourself of the SIBO. And then, highly important - don't discontinue eating the right way - gluten free, dairy free except what you can tolerate and sugar free as much as possible (check ingredient labels and look at the percentage of sugar. I shoot for 10% or less. It is quite amazing how much added sugar there is in products. If 10% or less is not to my liking of a product, I will add in some Stevia to help.
Best of you!