I gets fits of cough along with breatlnessness and weazing sounds almost daily,especially at night which only goes away after histamine, my xray,spirometry test are fine, but my cough is not going since over a year, what treatment should i follow nex?

Any cough lasting more that two weeks needs to be evaluated by a doctor. It would be prudent to see a lung doctor. It is not feasible to provide a meaningful opinion without examining you. Wish you good health!

You may have asthma or another cause related to these symptoms. Discuss a PFTs with a bronchodilator to assess improvement and your asthma plan. If a bronchodilator does not help significantly, a HRCT may be indicated. Avoid common allergens such as dust.mold,pollen.