Influenza, "the flu," is caused by a virus that infects the respiratory tract and is spread from person to person through coughing and sneezing. According to the Centers for Disease Control, the flu can cause serious problems for some, including anyone taking immunosuppressive drugs such as Imuran, Neoral, Purinethol, and Prednisone

In a recent study conducted in an IBD specialty clinic, it was found that 86 percent of the patients were taking or had taken immunosuppressive medication,...