Changing seasons bring running nose and sneezing. what will be the cause for the same? what will be the treatment for permanent cure of it?

Allergic rhinitis : More specifically seasonal allergies in this case. Identification and avoidance of the triggers is the best treatment, but not feasible for most of humanity. Non-sedating oral and intra-nasal anti-histamines, intra-nasal glucocorticoids, are the mainstay of therapy. Immunotherapy by an immunologist is your best bet at a true cure. Seasonal migration if covered by your health plan.