A friend of mine just found out that she is allergic to sulpher after she broke out in hives after taking medication with sulpher in it. SHe cleared up, bet then went out on Friday night and drank beer and then on Saturday started breaking out again. She didn't go out again for a week, went out again on a Friday night (after clearing up) and drank beer. Same thing she said that on Saturday she broke out again, so she thinks she is allergic to beer. Then someone told her today that there is sulpher in beer. I looked it up and saw something like sulpher iodine that comes from old beer or a yeast issue. Can any of you master brewers out there provide any deeper insight??