I experience a gag-like reflex but I think it is caused by my dentures. I lost most of my teeth to bulimia, later pregnancy and then dry mouth caused by bi-polar meds. It has really messed me up. I feel like a freak. And always there is a little voice that says"you did this to yourself". Get it checked out. But it may be hard to come out to your MD about the bulimia. Let me know what you decide to do.