S-Ppi-L Capsule SR

I am suffering from heavy coughing at night somehow from 3 weeks. During starting 2-3 days it was a very sore throat, i was not able to speak even.While coughing Initially it is a dry cough but after coughing sometime, it comes with mucus. It stops automatically when I vomit or after 10-15 mins. Or after it becomes chronic. I have taken azithromycin 6 tabs. And also taken fynal oz, dilosyn syrup and doxomax-12tabs.each after consulting a doctor. Doctor told it is a throat infection. During the course of fynal oz and doxomax, I felt okay. But after the course i.e from yesterday, the cough is back. I don't understand the possible cause. I am a smoker since 2 years (not heavy smoker, generally 2-3 cigarettes/day). Bt since the problem started, I have quit smoking.