Hi i am a 27 yr. old with cah non salt wasting diagnosed at about age 6. up until then i was always!!! sick Tonsilitus and pneumonia twice! the week i was supposed to get my tonsils out they diagnosed my cah. as soon as i was on the right amount of cortisone for a while i never got sick. til this day it is rare i get a cold or flu. i dont think it is the meds that are making your child have a lower immune system but the cah itself. in normal people when you are sick or under stress your body makes more cortisone to deal with it, but if your body cant make the right amount it gets sick quicker. so let your doctor know and maybe the meds need to be adjusted. good luck