- Is it possible your dog has eaten something that he/she shouldn't have?
- Is her stomach hard to the touch or soft?
- Has the vomiting been going on for a while or just one day?
If her stomach is hard it may be an intestinal blockage in which case she/he needs to see a vet. Also, if he has been vomiting for more than a day, I would get him checked too.
However, if it has just been today, you could give him some benedryl for the hives, and then the best treatment is just to starve him for 24 hours.
No treats, no food at all. You can leave a small amount of water but make sure she doesn't lap it up and make herself sick again.
After 24 hours, offer a bland diet of chicken with some rice in very small amounts and see how she gets on with that. If the vomiting continues or she starts to become lethargic or you noitce any unusual signs (you know your dog) then I would take her to the vet so that he can rule out parasite infection or an illness.
I really hope he/she feels better very soon.