I have been coughing for about 7 years. I have been to 3 doctors and been on meds for post nasal drip, asthma. I had my thyroid out in Oct; because it was enlarged and closing up my trachia but that didn't help. Have had xrays and cat scans and everything looks good. It seems to coming from my throat area. sometimes i cough so hard that i almost pass out. I'm really at wits end. Any suggestions?