Reglan if I remember right is for increasing motility of the stomach. If your doctor feels your nausea is due to delayed emptying he is probably trying to see if it helps.
Phenegren is a anti-nausea med. I had Nissen fundo and cannot vomit so I keep a prescription of it on hand at all times. The one I have is suppository style so it acts faster and doesn't interfer with the stomach when nauseated.