If you have a newborn younger than 3 months, call your child's pediatrician at the first sign of diarrhea.

In any child, bloody diarrhea or a case that lasts longer than two days also should prompt a call to the doctor.

While your child has diarrhea, make sure he or she drinks lots of fluids. A drink that contains electrolytes is best to help prevent dehydration. For young infants, continue nursing, and ask your doctor about giving extra fluids.