My 16 year old son has problems with his gag reflex. It clicks in when he's talking, during physical exertion and during inopportune times. He has allergies, sinus problems and has been examined by a local ENT and taken gastro testing but nothing shows up. What kind of other specialist should we seek out. This problem with his unwanted gagging is causing some very difficult problems in his young life at this time. If he talks too long, the gag reflex kicks in. When he practices his flute, same thing. When he works out physically, it kicks in. Would like some advice on this strange problem.