Spitting up is something many babies do after a feeding, but this alone doesn't mean your baby needs to switch formulas. Instead, look for signs like vomiting and diarrhea, which could signal that your infant is having an allergic reaction to milk-based formula, according to KidsHealth.org. Still, keep in mind that only 2 to 3 percent of babies have a true milk allergy or cannot digest lactose.
Look for signs of digestive distress. If your bottle-fed baby is struggling with seemingly painful gas post-feeding, every feeding, or you are noticing even more concerning side effects like bloody stool, severe irritability or a skin rash, take note. According to KidsHealth.org, these are common signs that baby may be allergic to cow's milk. Your baby may exhibit symptoms of a milk allergy as soon as a few days after first being introduced to a lactose-based formula. However, it usually takes time for a milk allergy to become evident to parents.
Consult your baby's doctor. If you suspect that your little one is suffering from a milk allergy, discuss your concerns with a pediatrician. Your pediatrician may ask you about family history and do a few tests, like a blood test and allergy skin test, to make sure he knows what is going on with your little one's digestive system. Sometimes another health concern is to blame for baby's symptoms, having nothing to do with formula.
Test a new formula. After assessing your infant's health, your pediatrician may recommend switching to a hydrolyzed formula, which is easier for babies to digest because the proteins are broken down into tiny particles. Or your doctor may suggest a soy-based formula; just be sure to seek medical advice before selecting this option for your baby. KidsHealth.org says that your little one's concerning symptoms should resolve in two to four weeks on the new formula.