If your baby is vomiting, has diarrhea, or is feeding poorly, it is possible that he may become dehydrated (doesn't have enough fluid in his body).
If your baby shows one or more of the signs listed below, call his health care provider right away:
has fewer than 4 to 6 wet diapers in a day
has dark urine that's almost brown in color
has fewer than 2 stools a day (A breastfed baby's stool can be quite loose. The number of stools can decrease after your baby is 4 to 6 weeks old. This is not a sign of dehydration.)
acts very sleepy or is hard to wake up
has a temperature of 100.4 degrees Fahrenheit or higher
has skin that feels dry or that stands up between your fingers when gently pinched
has sunken or dry eyes
has a dry mouth (Feel inside his mouth. A healthy baby's inner cheeks, gums and lips should feel wet.)
has a sunken look to the soft spots on the top of his head.