I have asked two doctors about the excact same question (with metroclopramide).
One of them said it will stop you from v* no matter if the reason is a stomach virus or even if you're pregnant!
The other doctor said no. He said that if you get a really hard bug or food poisening nothing will prevent vomiting. However, this doctor also told me that adults usually don't get very hard stomach bugs. Usually they only get d* or maybe v* once. Only small kids v* all night.
By the way, I see your location is Denmark? Are you Danish or do you just live there? Just wondering, because I'm Norwegian and I have never spoken with an emet in my mother tounge before. Feel free to post me a private message and say hello if you speek Danish.