My oldest son started vomiting last night and this has continued for several hours. I am suspecting food poisoning considering it happened a couple hours after we ate dinner out. These are some tips suggested by About.com to help your children deal with vomiting:
This is one of the more frustrating symptoms for parents, who often make things worse by pushing fluids too fast. If your child's vomiting is from a simple viral infection, while you do want to prevent him from becoming dehydrated, it is usually best to give frequent small amounts of fluid. An oral rehydration electrolyte solution is usually the best choice, and you can offer your child 1-3 teaspoons of fluid every 5-10 minutes. Even when vomiting a lot, they can usually handle this small amount of fluid. Popsicles are a good alternative.
As your child gets better and is vomiting less, you can increase how much you are giving him, for example, moving up to 1-3 tablespoons. After that, if he doesn't vomit for a few hours, you can increase the amount again to a few ounces at a time. If he begins vomiting again, give him a break for an hour or so and then try again and seek medical attention if he begins to get dehydrated.
