I Have Had This Cough Since February And Was Treated

I have had this cough since february and was treated with SEVERAL ANTIBIOTICS (|DUE TO INFECTION) i have been back to my dr again as on my left side behind my tonsil i have this aweful scratchy tickling which effect me at nite and during the day he prescribed me omeprazole but i need to take a cough suppressant as it keeps me awake most of the nite and sometime in the day this is my 3 day of omeprazole Please help