I've had 4 or 5 MRI scans and never had any barium with them. Okay, I googled it, 'cos something was niggling at me: an MR
E does use barium, at least sometimes. For my scans, I did have to drink a litre of solution half an hour beforehand, but it was never barium. I think if your friend has an MRI/MRE, she should clarify her hospital doesn't use barium beforehand.
www.insideradiology.com.au/pages/view.php?T_id=75#.VfMihhFViko