An allergy to dairy should not be confused with lactose intolerance. A true allergy involves the body's immune system. When the allergen, such as dairy, enters the body the immune system treats it as an unwanted intruder. An intolerance to a food is due to the body's inability to process the item. With lactose intolerance, the protein lactose can't be adequately broken down and causes several digestive consequences. Dairy allergies are often outgrown before the end of childhood, but it may persist through adulthood.
Immediate Signs
The Mayo Clinic suggests that almost immediately after consuming milk, an individual can develop hives, wheezing and vomiting. Hives appear anywhere on the body as slightly raised, red and itchy lesions. These same symptoms can develop after eating any dairy product.
Digestive Symptoms
A number of digestive symptoms can develop several hours after ingesting dairy. This includes loose stools, diarrhea and abdominal cramps. In some cases, there may be blood in the stools.
Respiratory Symptoms
Because the immune system is provoked with a dairy allergy, respiratory symptoms can appear. This includes runny nose, coughing and wheezing. In severe allergic reactions, an individual may experience anaphylactic shock, where the airways are closed and blood pressure drops suddenly. Emergency treatment is necessary to prevent death from suffocation. This type of reaction to dairy is not common.
Infant Signs
In addition to all other dairy allergy signs, an infant may present different symptoms. Infants may be described as having colic. The infant may spit up or vomit more frequently directly after a feeding or even several minutes or hours later. Fussiness and gassiness are other possible signs of infant dairy allergies. Breastfed infants can have the same signs of a dairy allergy. Mothers can identify if the dairy is the source of the infant's symptoms by keeping a food log. It is often suggested that she avoid dairy while keeping the log to see if the infant's symptoms disappear.
Facial Symptoms
Some individuals may develop watery eyes following the consumption of dairy. An itchy rash can appear on the skin, especially around the mouth, according to the Mayo Clinic.
