My Girlfriend gets this every night. It's crazy, I wish she'd just smoke a bowl but she 'doesn't like the taste'. Drs. have no idea what's wrong, she just lives with it. Try smoking man, honestly it might help. If not, take some Pepto.
if its in the morning its due to the effects of going to bed high with no food. if you dont give in to the munchies and go to bed with cottonmouth/empty stomache, you can cause a cyclical vomiting episode due ti stomache linning irration. dogs have this sometimes, if you have ever seen your dog hawk up in the morning this is the reason. eat a small treat and a big glass o water b4 bed, this should help the irration a bit