Several of your symptoms sound like mine. I have been actively treating my SIBO for the past few weeks and have had amazing improvements. I used enteric coated peppermint oil with caraway and oregano oil, and am now using 250mg grapefruit seed extract. My post nasal drip is gone, my skin is clearing, and my digestion is improving constantly. I use HCl and after the ECPO I have been able to reduce my dosage from 5 caps to 2 caps per large meal. Apparently, ECPO can increase stomach acid production. Also, I have recently found information that suggests that Iodine deficiency can contribute to low stomach acid. Please look thru a few of my posts as I have included several links that you may find interesting.