Chronic sore throat is probably caused by acid reflux which can be caused by a lot of GI issues. A lot of people with SIBO suffer from it.

Drinking water with some baking soda in it can bring temporary relief. I use Gaviscon Advance for bad episodes and that helps me out too. Unfortunately I haven't been able to pinpoint the cause of it.

A lot of people say it can be caused (paradoxically?) by low stomach acid, but Betaine HCL supplements didn't help me at all. I try my best to get by without medicines that inhibit stomach acid because they can cause long-term problems and make SIBO worse.

I also find, strangely, that the worse my SIBO symptoms get, the better my reflux gets and vice versa. I wonder if anyone else experiences something like that..