Suffering from Allergy for 8 years.

I am suffering from some allergy which is not known to me. I consulted a doctor and he prescribed me medicine and nasal spray which actually controls my allergy but once i stop this medication it start happeing to me again. Medicine i take are citrazine or Montair FX Furamist nasal spray. I found my allergy little wierd because if i stay some other town it never happens and when i am at my home Delhi it has to happen. I cant take rice, curd, salad, or anything cold beacause it activate my allergy aggressively.  Wheareas if i am staying some other town i can eat anything, nothing happens. I am sufferibg from this allergy since long more than 8 years now. During my graduation  I use to stay in hostel (Bhopal) altogether different state but whenever i use to come home this allergy gets activated automatically. Please suggest me best..