What Causes Constant Coughing While On Methylprednisolone And Zithromycin?

I started taking methylprednisolone today for bronchitis. I am coughing uncontrollably . I wasn t coughing near as much before to the point of choking.I am also taking zzithromycin, but the amount of the steroid seems to be what is triggering it. Is this normal?