I even felt a difference with as little as up to 6 drops of Lugol's a day (each drop 6.25 mg.) but if I remember correctly it was at 3 drops.
I went up to 20 drops a day and noticed my body was sort of "stopped up" then I had a Gallbladder attack and had to Liver Flush a few times. I also did it by Coffee Enemas. After that the periods went back to normal. I am presently on 9 drops of Lugol's a day.
Iodine is known to loosen Gallstones, if you have them.
I would start Liver Flushing if you've never done it before. It seems like keeping the Liver clean keeps things flowing. coffee enemas are good for cleaning out the toxins too.