Red_34: sulfites are preservatives distilled from sulfurous acid. The FDA banned their use on fresh produce in 1986 because they can induce severe allergic reactions. However, they are still used on some dried items such as raisins, apricots, & prunes. Why ROWASA's manufacturers decided to use them beats me! Sulfa is sulfanilamide, a pharmaceutical drug that combats bacterial infections such as those that stem from serious burns. It is also used as a bonding agent in the earliest 5-ASA drugs, generic sulfasalazine. It is not the most tolerable med to ingest, either-- so a lot of IBD patients had problems taking Azulfidine (yours truly) & do better since Asacol & then Colazal came on the market. / Old Hat (nearly 30 yrs with left-sided UC; currently on 3 X 3 Colazal daily for July flare in descending colon, which is responding)