The milk alergy develops when the immune system in babies errantly finds the milk protein as hazardous and struggles fighting it off. This function generates the allergic reaction which may end up leaving the baby finicky and petulant besides causing the stomach upset and several other symptoms.

Many of the babies, who are allergic to the cow’s milk, may also be allergic to sheep’s milk or goat’s milk. While some are even found to be allergic to proteins in soy milk. However, the baby being breastfed pose to be at lesser risk of allergic reactions as compared to the baby who is prescription fed. Yet the researchers have not fully understood the reason why some babies exhibit milk alergy whereas other not. Here the alergy may be due to genetic reasons.