Hello Krishnakant, Thank you for asking at HCM. I went through your history. I conclude that you are having recurrent bouts of sudden severe dry cough for last 5 years. Your chest X-rays are normal & your physicians have ruled out tuberculosis. However, I would like to know more about your problem, like - how many times in a month you have such episodes? Are they more at day or more at night? Are they more at home or at working place? Do they occur more in some specific season or not? Can you correlate any environmental exposure to such episodes? Do you have any nose or throat symptoms? Have you ever had difficulty in breathing? etc. This will help more to reaching towards diagnosis. I would suggest you Spirometry with reversibility testing. This is necessary to diagnose or rule out asthma. (Asthma may be due to allergy) I assume that you have not had any breathing difficulty. If your spirometry suggests asthma, it will be the cause of your coughing bouts. However, if spirometry is normal, the cause of your cough may be outside chest. Hope this will help you. Wish you best of the health. Regards.