I had supraglottitis about 5 months ago. Did MRi and biopsy and results were negative. Since the infection i have cough that is rather bad and retching. Only white foamy or colorless phlegm (or saliva). Copious amount and after quite a number of coughs, I feel better. Sometimes fried food causes it as it is swallowed and sometimes it feels ticklish and then cough comes on till the saliva/phlegm is got rid of. What is the cause and what medication do i need?