I get a mild case of hives due to an allergic reaction. Benedryl for a couple of days takes care of it. I also react to contrast dyes for kidney stones the same way. I think I am in the minority. Most people do not react.
I had no reaction at all, at least none that I noticed. I suppose it did what it was supposed to do.
You can't fly for several days after because the airport screeners will think you are a nuclear bomb in disguise.
Oh, and you glow in the dark for a week or so............:-)