Anyone Help? My son has barky cough for hours with no relief

[jonesgirlsells]

My son has asthma and I am familiar with the "croup" cough.  But every two weeks for the past 2 months and right now he is coughing with absolutely no relief for hours.  He is on hydrocodene, prednisone, nebulizer, I have a vaporizer, his asthma meds (advair) and nasonex.  I also gave him Mucinex MD.  Yesterday he coughed for over 8 hours straight.  Finally when they called in the hydrocodene, it slowed the coughing in between. (like I can count almost to 1 in between his coughing in the other room right now.)  Yes that is a one (1).  Last night he finally got to sleep at about 10:30pm but woke coughing again at 3:45am.  Gave more hydrocodene and he stopped coughing at about 5:45 til about 6:30am.
It is a nightmare.  Wearing us both out.
I took him to the doctor Monday and he also had strept throat.  Now it is the chronic cough.  I am going back to the doctor again today.  I considered whooping cough but can the peroids in between coughing be 2 weeks??
He doesn't have a fever.  I'm at a loss????