Casein allergies are allergies to casein, a protein found in mammal milk, like that from goats and cows. Patients with casein allergies may identify them as dairy allergies, but in fact they are reacting to a specific dairy protein, which means they could experience allergic reactions to supposedly “dairy-free” foods that contain casein extracted from milk. If symptoms of allergies emerge after eating milk, cheese, and other dairy products, it is important to get allergy testing to find out what, specifically, the patient is reacting to.
Patients with casein allergies can experience a variety of reactions. Their skin may break out in rashes and become very dry, and they can also develop numbness and tingling around the lips and nose. Some patients vomit or have diarrhea. In rare cases, casein allergies are so severe that they cause anaphylaxis, where the airways start to close, the patient struggles to breathe, and there is a risk of death if prompt treatment is not available.
In addition to appearing in milk, this phosphoprotein also appears as a food additive and binder in a variety of products, from non-dairy creamer to nutritional shakes. Patients who appear to have milk allergies can get a detailed allergy test to see which proteins in milk they react to, so they know what to look for on food labels. In addition to casein, whey is a common culprit. It is important to read food documentation carefully to check for casein, as even trace amounts can cause allergic reactions.
For someone with casein allergies, eating out at restaurants can be challenging. Many restaurant staffs are familiar with the concept of dairy allergies and can accommodate them, but may not understand that traces of casein in things like pre-packaged mixes could be a problem for diners, as could foods prepared on shared surfaces. A deli making sandwiches, for example, may slice meat and cheese on the same equipment, exposing diners with casein allergies to the risk of ingesting casein with their food.
Individuals with casein allergies should also be careful in hospital settings, as hospital kitchens often use industrial food mixes that may contain casein as a binder or filler. The patient's doctor should make sure the kitchen staff and nutritionist are aware of the allergy and the risks, so they can select appropriate foods for the patient. At any signs of allergic reactions, a nurse should be called immediately to provide treatment, and the patient should provide a list of anything he has recently come into contact with so the hospital can identify the source of the exposure.