My son has frequent vomiting in the morning - 16 yrs old. He also has middle GI pain, diarrhea, generalized nausea, light-headed episodes. He has undergone colonoscopy, endoscopy, a myriad of fecal tests, gallbladder tests, all have been found normal (for which I'm grateful) however, he is still having the problem. It is not always bad but will be very bad for a few days, then he's better, then it's back. We've taken dairy out of his diet, it seems to help some. What else can we do?