Definition of Diarrhea in Formula-Fed Infants

• Formula-fed babies pass 1 to 8 stools per day during the first week, then 1 to 4 per day until 2 months of age. 
• The stools are yellow in color and peanut butter in consistency. 
• Formula-fed newborns have true diarrhea if the BMs abruptly increase in number or looseness and persist for 3 or more stools, become watery or very runny, contain mucus or blood or develop a new bad odor. 
• Other clues to diarrhea are poor eating, acting sick or a fever. 
• After 2 months of age, most infants pass 1 or 2 stools per day (or 1 every other day) and no longer appear to have mild diarrhea.