chronic throat clearing after eating

hi i am 30 yrs old male from india.i am having some problem since more than 1.5 years.i do throat clearing all the time .more throat clearing after eating. as if a small mucus is stucked in my throat,which is not comming out.i was admitted for this in hospital.they have lots of tests including ct scan of chest,mri scan of throat,barium meal,endoscopy,24 hr esophagal ph monitoring,usg,blood tests.all are normal.no GERD.what should i do now?
please help me.

e thing i must tell u.this started at sep.2009.at that time,one day i sprayed baygon spray(for killing bugs and moquitoes) in my room ,and then i had to sleep in that room.since then my problem increased.there was some smell of spray.

i am doing this for 1 and half years.now i cant cough and hawk anymore.pls help. ..