Consult an ent physician.. rule out if you have a nasal polyp or DNS or sinusitis. Take tab montek lc for relief.. and skin prick test for identification of allergen.

Tab Montair Lc once at night. Syrup Alex 2 tsf thrice daily after meals. Also get Serum IGE

To find out which allergen is responsible for your condition is very difficult without testing. You can take anti-allergic and get CBC with ESR, Mantoux test, chest xray done. Give sputum for AFB examination and C/S. Also take Tab fluconazole 150 mg for 3 days.. Also tell me if you have fever or not? If it is then 4 Hourly and share all report with me on Practo consult direct Delhi zone... All d best

Best treatment would be to find allergens causing symptoms and to avoid it...over the counter antihistaminics will be beneficial to you...Consult nearest allergy clinic for skin prick test and other modalities of investigations in which they will test you for various allergens and find out to what you are allergic...and they treat you with diluted doses of that allergen to desensitise your body to that allergen...good luck.