I did not there was a medication to prevent from dehydration - when mine got sick, she was vomiting for two,three days as well as diarrhea started with vomiting (the vet told me to watch her to see if she stops getting sick), and when it went to the third day, I brought her to the vet and found out that she had an infection on her pancreas. She had to stay overnight for IV etc. I'm very fortunate to have a vet emergency room that opens from 5pm until your regular vet opens (well, they are also very costly..).
