Passing out waking up covered in vomit

Dear Ask The Doctor: I was on a bus the other day and was feeling extremely dizzy to the point where I couldnt stand up. Then next minute I was waking up on the floor covered head to toe in vomit. I guess I passed out. Why would something like this happen out of no where?

Dear Kristen: Its impossible to pin point an exact answer with the information you have provided. It could be from anything from lack of hydration to something you ate for the reason you passed out. I would suggest you make an appointment with your family doctor to get some tests done.