hi , i got thick mucus in nose from past 6months , it s not too much to disturb my daily routine , but have to clear my nose at least twice a day , and it s little excess before going to sleep and i have to clear it . i have habit of smoking 2 cigarettes a day , i tried anti histamines and nasal decongestants but it s only effective in treatment period , once again same thing starts . please help me with what might be the cause and cure