many (most in fact) causes of bronchitis are viral so the z-pack may have done nothing. the prednisone may be helpful for a reactive/allergic cough but this does not cure a virus either. neither medicine nor your disease should have a direct effect on your period so you may need to consult your doctor yet again to take your evaluation and treatment up another notch.
zpak for bronchitis then methylprednisolone for lasting symptoms. period for 9 days still coughing. i was prescribed azythromycin for bronchitis after having cough for several days. then called dr and got methylprednisolone after complaining still had cough and tickling sensation in chest when coughing. started menstrual period on day 3 of zpak and am still on it 9 days later. and finished med this morning and still have cough and bleeding.