Hi. Thanks for your query. Noted your history of nausea and vomiting for 8 weeks now, multiple labs normal, gastric emptying study normal, endoscopy showed hiatal hernia and was put on Prilosec. Your early morning vomit was yellow and now it is green - wants to know why. The vomiting of yellow or green is bile and it indicates that you have bile reflux from the duodenum to stomach and from stomach to up and out. There is no difference whether it is green or yellow. So no worry as far as the color is concerned. The problem is also not much of hiatal hernial, it is the bile reflux that is causing you all the problems. I would advise you the following: Contact your Doctor and discuss about this to get a prescription of Domperidone or so. This may regulate the vomiting. Other tests should be done to see for the cause as you are suffering from 8 weeks, these include barium study to see whether there is obstruction to the small intestines, scarified duodenum, pancreatic pathology and so on. Also needed is Ultrasonography of the abdomen, CT scan and so on as per the clinical picture and examination. A proper diagnosis is going to help for a better plan of management.