The only thing that you can really do at home is use some plain pedialyte in very small amounts to rehydrate him. Some emetrol might also help with the nausea. It's a baby anti-nausea medication.
If he won't drink the pedialyte, you can try to administer it with a syringe (no needle). If he STILL won't take fluids, I would suggest a call to your vet in case he needs sub q fluids.
Let me know if you have more questions.