Whether a reaction to a dairy product is an insensitivity or a true food allergy depends on the symptoms. A dairy allergy is the body's response to the intake of one or both proteins found in cow's milk: whey and casein.
Symptoms
Symptoms of a dairy allergy are histamine-based. The proteins in cow's milk (casein and whey) begin to alert the body to the danger, leading to inflammation and other physical symptoms in an allergic person. Some symptoms may present themselves within minutes of ingesting dairy products and other foods containing milk proteins. Early symptoms include wheezing, digestive problems and vomiting. Other symptoms may not become evident for hours. Some of the most common include diarrhea, itchy rash (around the mouth), wheezing and/or coughing, abdominal cramping and runny nose.
Casein and Whey
Casein is a protein in cow's milk that is found in most dairy products, as well as in many non-dairy foods. Non-dairy foods include breath mints, high-protein drink mixes, cereals that have been fortified, processed meats, nutrition bars and some salad dressings. Common symptoms of an allergy to casein include skin rash and the more subtle symptom of fatigue. In allergic patients, the immune system reacts to the casein by triggering histamines to alert the body. Inflammation may result.
Anaphylaxis
The most dangerous (and most rare) allergic reaction to cow's milk is anaphylaxis, a narrowing of the airways and the restriction of breathing. Other symptoms include flushing of the face, itching, difficulty breathing, a severe drop in blood pressure and shock. If you suspect anaphylactic symptoms, seek emergency medical care immediately, as an epinephrine shot will be necessary.
