Hi,
After a month or so of lurking, I am finally posting something! I don't have any problems w/ beans, but my husband does so we keep Beano on hand.
I looked up Beano in the Physician's Desk Reference from 1991(a drug reference book). According to it, Beano is derived from a mold known as Asperigillus Niger. As of 1991, there were no known adverse reactions to it. The PDR does say that "it is conceivable that mold-sensitive persons could react. Penicillin-sensitive persons might be particularly suspect." Someone who has a more recent PDR handy might want to see if there is more updated information.
I hope this helps.
Lisa
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