I was on about 7.5 mg/day before I jumped to 125 mg. Was great for me. Only problem was I went to gung-ho on the companions and took too much magnesium and Vit. C. Higher doses of Iodine are great. It's up to you whether you can make that jump. It works for most people. If you get too bad of a detox, pulse and do salt flushes.
I don't know about the Antibiotic interference. I will let others chime in on that...iodine should be the only "antibiotic" you should ever need!