If you are allergic to cow's milk, babies will often vomit or have diarrhea after drinking formula or cow's milk. However, that is not the only symptom. There are other symptoms or signs that can appear in babies who are allergic to cow's milk. Cow's milk allergy is one of the most common types of food allergies in infants. The risk of an allergic baby will be higher if one or both parents also have a history of allergies. In addition to drinking formula milk directly, your child can also show an allergic reaction when he consumes processed cow's milk products or drink breast milk from mothers who consume cow's milk. Milk allergy is often equated with lactose intolerance because the symptoms of these two conditions are similar. In fact, both are very different conditions. Cow's milk allergy occurs when the baby's immune system overreacts to the protein in milk, whereas lactose intolerance occurs when the baby has difficulty digesting lactose (the n