Cow’s milk allergy A food allergy is an exaggerated reaction of the immune system to a specific food or food group, causing a range of symptoms— from a rash; to abdominal cramps; to diarrhea; to difficulty breathing or swallowing due to swelling of the lips, mouth, throat, and airways. In extreme cases, it may cause a life-threatening reaction called anaphylaxis, with sudden breathing difficulty and collapse.
Almost any food can cause an allergic reaction, although dairy products, nuts, eggs, seafood, and wheat are common triggers.
A food allergy is different from a food intolerance, in which symptoms arise from food toxins, problems with digestive enzymes, or the direct action of chemicals in the food.
The most effective treatment for an allergy is to avoid the problem food. People with a severe allergy may be advised to carry an epinephrine autoinjector for emergency treatment