Hi, Noted your short history of running nose and phlegm for the last 4 months, recently given up smoking in a hope to improve the situation, 2 X-ray chest were normal. Running nose is indicative of rhinitis that is inflammation of hte nasal mucosa responding too much to the situation. This can be due to infection or allergy. Too much mucus secretion is phlegm. I would advise you the following: Since it is about 4 months that your are suffering it is better to consult an ENT Surgeon for ENT endoscopy to see for the cause, the changes and aftereffects. CT scan of sinuses to see whether there is primary or secondary sinusitis. All this will lead to a proper diagnosis. Also watch for the foods, beverages, factors in atmosphere, temperature around to see for the instigating and enhancing factors which you have to strictly avoid as prevention is better than cure. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. T. Chandrakant, ENT & General Surgeon