I Cough All The Time. Have Seen ENT, Lung Doctor,

I cough all the time. Have seen ENT, Lung Doctor, allergies testing and G I Doctor. Do not have nasal drip and yes have germ but taking mess for acid reflux. Still have critic cough to the point I am going to pass out. I had all work ups available and even a mayo clinic consult Still have this caught. Any new ideas?