When my son has wheezing and coughing, the pediatric normally

prescribe pulmicort and xopernex, predinisone sometime was also prescribed, but we only used it when the pulmicort did not work...Most of the time pulmicort worked... Last time when we saw the specialist, we were prescribed advair (100/50), my son used it and the lung function improved only a tiny bid. The specialist thought it was nothing, so change to symbercort, but his lung function did not improve at all, so the doctor think the asthma is not undercontrol, he ordered CT. I will try to talk to him about this. thanks for the suggestion.