I'm not sure why, but Dr. Clark has changed her iodine. I have a bottle from her store that is 5% , yet her website now has Lugol's at 2%. I think we need to see what these pros here on the forum have to say about this before we talk about how much to take.
I have the 5% and I simply take four drops- two times a day. This seems to work well for me. I also eat seaweed with mine.