Milk allergy and lactose intolerance are two very different health concerns, as indicated by the Food and Drug Administration. An actual milk allergy typically affects children until the age of 3, but it can persist through adulthood. Differentiating an allergy from intolerance is done by examining symptoms. An allergic reaction to milk will involve the immune system because the body is reacting to the milk as if it is a dangerous foreign agent. Milk intolerance typically affects only the digestive system due to the individual being unable to process the milk protein (lactose).
Hives
The Mayo Clinic suggests that hives may appear on the body immediately or several minutes after consuming milk when an allergy exists. Hives are raised, red lesions that can often be itchy. Allergic responses are very individualized, so one person may have hives on the torso while another experiences them on the face.
Respiratory Symptoms
The consumption of milk can lead to a few respiratory symptoms of allergy. This includes wheezing and coughing. A respiratory response to milk consumption does not occur in an individual with only a lactose intolerance. Experiencing this type of reaction is a definite sign of allergy. Very rarely, this reaction can become exacerbated by an anaphylactic response. Anaphylaxis is a potentially life-threatening response where the airways become narrowed and breathing becomes extremely difficult. Emergency treatment is necessary for this type of allergic reaction.
Digestive Symptoms
Digestive symptoms of milk allergy may take longer to appear. These are similar to symptoms of lactose intolerance. Examples include vomiting, diarrhea with or without blood and abdominal cramping.
Facial Symptoms
Facial symptoms may take longer to appear in an individual allergic to milk. These include a runny nose, watery eyes and the development of a rash around the mouth. The rash is often itchy.
