What is the suitable dose of Xifaxan for small intestinal bacterial overgrowth?

Hello doctor,

I was diagnosed with small intestinal bacterial overgrowth (SIBO) four years before based on a hydrogen breath test and was treated with Xifaxan 550 mg three times a day for two weeks. The treatment seemed to help. However, my SIBO symptoms seemed to have returned around three month back. From the time of my first treatment, I had become uninsured and tried to treat the SIBO recurrence with some natural remedies. These helped for a while, but my SIBO symptoms have fully returned. Recently, while traveling overseas, I got some Xifaxan 200 mg tablets, as the 550 mg of Xifaxan was unavailable. However, paying out of pocket for the 550 mg of Xifaxan would not be an option since the tablet is quite expensive. Here is my question:

1. What would be the correct dose of Xifaxan tablets to treat my SIBO recurrence?
2. Is it 600 mg three times a day for two weeks (1800 mg per day) or 800 mg (1600 per day)?

Thank you.