I just saw this, and I wanted to add-- I have been having this for the last 7 years, but it comes and goes. It is quite unbearable at times, and then it gets bearable. I have also done lung, ENT and other tests-- nothing has come up so far. It has been really taking a toll on my life though now, since for the past 2 months, the symptoms have been continuous, as opposed to a few years back when the symptoms came, stayed for a month or so and then went. Curious, if there have been any other diagnoses of this?