Investigating Blood in Stool: When to Call the Doctor

Finding red streaks or blood in your baby's diaper can be incredibly alarming for any parent.

If your baby is old enough to eat solid foods, consuming deep red items like beets, tomatoes, or food dyed with red coloring can temporarily mimic the appearance of blood in the digestive tract. However, if solids aren't the culprit, blood in the stool typically points to a few common medical variations. In young infants, the most frequent cause is a food protein allergy or intolerance, most notably a Cow's Milk Protein Allergy (CMPA), which causes localized inflammation and tiny tears in the lining of the intestines. Other potential causes include small anal fissures (tiny tears in the skin from passing a firm stool) or an underlying gastrointestinal infection. Your pediatrician can perform a quick test on a stool sample to confirm the presence of blood and guide you through dietary changes or treatments to heal your baby's gut.