I just threw up my barium swallow. what should i do?

Try again: If it was just a couple swallows give it another try slower pace ... If it was good volume call the center and tell the and ask to reschedule.

Call your MD: Continue drinking the barium, try to hold it down, because that's the way the radiologist will be able to see your digestion tract and bowels in the x-ray. If you can't hold it down, make sure and call your doctor's office before the test to inform them.

Prob. isolated event: It sounds like either you became nauseated from the barium meal or have slow gastric emptying if occurred a while after the meal. If self limited event without any other issues or symptoms, probably should forget about the incident. Barium is inert and usually does not cause any problems.