You need to meet an ENT Specialist immediately to ascertain the cause of this cough. Possible diagnoses may be reflux esophagopharyngitis / chronic sinusitis induced post-nasal drip / allergic rhinobronchitis
Next Steps
Use this app to find a good ENT Specialist near you or if you are able to make it, drop into my clinic Healthcare@Basaveshwaranagar. You also have a third option to consult me online using the private online consult option, but you need to be using the Practo app on your smartphone to do so.