If . If she is well-appearing, alert, happy, but throwing up, you can try giving tiny sips of pedialyte to keep her hydrated. If she is acting ill, unable to keep any fluids down for 6 hours or more, or has green or bloody vomit, call her doctor or go to the emergency room. Another reason you should call your child's doctor immediately or go to the emergency room is if you see any signs of dehydration. These signs are: -dry mouth -few or no tears when crying -excessive fussiness -fewer than 3-4 wet diapers/day -no urination in 6-8 hours -sunken soft spot -dry, wrinkled or doughy skin -appears weak or limp -decreased alertness or increased sleepiness -rapid breathing or fast heart rate.