I'd say "sports drinks" like Gatorade would be the way to go. Gives the hydration of water with the electrolytes lost via vomiting. Grace had something like that a couple of weeks ago, and I plied her with Gatorade to prevent the dehydration. I don't know about the sugar content though. You might have to go with something like Pedialyte. They gave that to my Dear Old Dad when he was ailing.
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