My daughter has been hospitalized for dehydration for glutenings. She has Eosinphilic Esophagitis too.
Really it is a trip to the urgent care and getting anti nausea drugs quickly. Usually a shot as she can't keep any fluids down. If we miss that window of time she has needed an I.V. for about 3 to 4 days. The recent release of the anti nausea drug wused for chemo patients has helped a lot.