I would have this dog examined by your veterinarian to make sure this is not a recurrence of pancreatitis. Your dog may need to be on a special diet as well to prevent the vomiting--your veterinarian can help you determine if this is necessary. Until your appointment you can try giving Pepcid AC. The dose is 0.5 milligrams per kilogram of body weight given by mouth every 12 hours. Pepcid comes in 10 milligram tablets.
Call your vet, and go to your local pet store and see what they have to offer.
I give my dog dry bread but you should take your dog to the vets