Hives scream toxins coming from the liver.
Have you done any liver flushes?
There was a lady on this forum that was stung by a couple dozen bees when she was in her teens.
When she was much older, she did some Liver Flushes and by the 3rd flush, she got hives.
The liver stores toxins that can kill us when the amount is too high in the blood and these can release later, especially after flushing out the liver stones .
The Iodine could be causing some toxins to come out that you are allergic to.